Corrected buffer overflow during automatic checkpoint in fast-import.
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index c120239ef34b150e3d4b94b6815714a8a0c33e23..ad476f7c689262ce54c761615eac1d82355b33f9 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -1,26 +1,87 @@
 /*
  * Copyright (C) 2005 Junio C Hamano
  */
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <signal.h>
 #include "cache.h"
 #include "quote.h"
 #include "diff.h"
 #include "diffcore.h"
+#include "delta.h"
 #include "xdiff-interface.h"
+#include "color.h"
+
+#ifdef NO_FAST_WORKING_DIRECTORY
+#define FAST_WORKING_DIRECTORY 0
+#else
+#define FAST_WORKING_DIRECTORY 1
+#endif
 
 static int use_size_cache;
 
-int diff_rename_limit_default = -1;
+static int diff_detect_rename_default;
+static int diff_rename_limit_default = -1;
+static int diff_use_color_default;
+
+static char diff_colors[][COLOR_MAXLEN] = {
+       "\033[m",       /* reset */
+       "",             /* PLAIN (normal) */
+       "\033[1m",      /* METAINFO (bold) */
+       "\033[36m",     /* FRAGINFO (cyan) */
+       "\033[31m",     /* OLD (red) */
+       "\033[32m",     /* NEW (green) */
+       "\033[33m",     /* COMMIT (yellow) */
+       "\033[41m",     /* WHITESPACE (red background) */
+};
+
+static int parse_diff_color_slot(const char *var, int ofs)
+{
+       if (!strcasecmp(var+ofs, "plain"))
+               return DIFF_PLAIN;
+       if (!strcasecmp(var+ofs, "meta"))
+               return DIFF_METAINFO;
+       if (!strcasecmp(var+ofs, "frag"))
+               return DIFF_FRAGINFO;
+       if (!strcasecmp(var+ofs, "old"))
+               return DIFF_FILE_OLD;
+       if (!strcasecmp(var+ofs, "new"))
+               return DIFF_FILE_NEW;
+       if (!strcasecmp(var+ofs, "commit"))
+               return DIFF_COMMIT;
+       if (!strcasecmp(var+ofs, "whitespace"))
+               return DIFF_WHITESPACE;
+       die("bad config variable '%s'", var);
+}
 
-int git_diff_config(const char *var, const char *value)
+/*
+ * These are to give UI layer defaults.
+ * The core-level commands such as git-diff-files should
+ * never be affected by the setting of diff.renames
+ * the user happens to have in the configuration file.
+ */
+int git_diff_ui_config(const char *var, const char *value)
 {
        if (!strcmp(var, "diff.renamelimit")) {
                diff_rename_limit_default = git_config_int(var, value);
                return 0;
        }
-
+       if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
+               diff_use_color_default = git_config_colorbool(var, value);
+               return 0;
+       }
+       if (!strcmp(var, "diff.renames")) {
+               if (!value)
+                       diff_detect_rename_default = DIFF_DETECT_RENAME;
+               else if (!strcasecmp(value, "copies") ||
+                        !strcasecmp(value, "copy"))
+                       diff_detect_rename_default = DIFF_DETECT_COPY;
+               else if (git_config_bool(var,value))
+                       diff_detect_rename_default = DIFF_DETECT_RENAME;
+               return 0;
+       }
+       if (!strncmp(var, "diff.color.", 11) || !strncmp(var, "color.diff.", 11)) {
+               int slot = parse_diff_color_slot(var, 11);
+               color_parse(value, var, diff_colors[slot]);
+               return 0;
+       }
        return git_default_config(var, value);
 }
 
@@ -33,7 +94,7 @@ static char *quote_one(const char *str)
                return NULL;
        needlen = quote_c_style(str, NULL, NULL, 0);
        if (!needlen)
-               return strdup(str);
+               return xstrdup(str);
        xp = xmalloc(needlen + 1);
        quote_c_style(str, xp, NULL, 0);
        return xp;
@@ -150,7 +211,7 @@ static void emit_rewrite_diff(const char *name_a,
        diff_populate_filespec(two, 0);
        lc_a = count_lines(one->data, one->size);
        lc_b = count_lines(two->data, two->size);
-       printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
+       printf("--- a/%s\n+++ b/%s\n@@ -", name_a, name_b);
        print_line_count(lc_a);
        printf(" +");
        print_line_count(lc_b);
@@ -164,7 +225,7 @@ static void emit_rewrite_diff(const char *name_a,
 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 {
        if (!DIFF_FILE_VALID(one)) {
-               mf->ptr = ""; /* does not matter */
+               mf->ptr = (char *)""; /* does not matter */
                mf->size = 0;
                return 0;
        }
@@ -175,24 +236,360 @@ static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
        return 0;
 }
 
+struct diff_words_buffer {
+       mmfile_t text;
+       long alloc;
+       long current; /* output pointer */
+       int suppressed_newline;
+};
+
+static void diff_words_append(char *line, unsigned long len,
+               struct diff_words_buffer *buffer)
+{
+       if (buffer->text.size + len > buffer->alloc) {
+               buffer->alloc = (buffer->text.size + len) * 3 / 2;
+               buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
+       }
+       line++;
+       len--;
+       memcpy(buffer->text.ptr + buffer->text.size, line, len);
+       buffer->text.size += len;
+}
+
+struct diff_words_data {
+       struct xdiff_emit_state xm;
+       struct diff_words_buffer minus, plus;
+};
+
+static void print_word(struct diff_words_buffer *buffer, int len, int color,
+               int suppress_newline)
+{
+       const char *ptr;
+       int eol = 0;
+
+       if (len == 0)
+               return;
+
+       ptr  = buffer->text.ptr + buffer->current;
+       buffer->current += len;
+
+       if (ptr[len - 1] == '\n') {
+               eol = 1;
+               len--;
+       }
+
+       fputs(diff_get_color(1, color), stdout);
+       fwrite(ptr, len, 1, stdout);
+       fputs(diff_get_color(1, DIFF_RESET), stdout);
+
+       if (eol) {
+               if (suppress_newline)
+                       buffer->suppressed_newline = 1;
+               else
+                       putchar('\n');
+       }
+}
+
+static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
+{
+       struct diff_words_data *diff_words = priv;
+
+       if (diff_words->minus.suppressed_newline) {
+               if (line[0] != '+')
+                       putchar('\n');
+               diff_words->minus.suppressed_newline = 0;
+       }
+
+       len--;
+       switch (line[0]) {
+               case '-':
+                       print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
+                       break;
+               case '+':
+                       print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
+                       break;
+               case ' ':
+                       print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
+                       diff_words->minus.current += len;
+                       break;
+       }
+}
+
+/* this executes the word diff on the accumulated buffers */
+static void diff_words_show(struct diff_words_data *diff_words)
+{
+       xpparam_t xpp;
+       xdemitconf_t xecfg;
+       xdemitcb_t ecb;
+       mmfile_t minus, plus;
+       int i;
+
+       minus.size = diff_words->minus.text.size;
+       minus.ptr = xmalloc(minus.size);
+       memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
+       for (i = 0; i < minus.size; i++)
+               if (isspace(minus.ptr[i]))
+                       minus.ptr[i] = '\n';
+       diff_words->minus.current = 0;
+
+       plus.size = diff_words->plus.text.size;
+       plus.ptr = xmalloc(plus.size);
+       memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
+       for (i = 0; i < plus.size; i++)
+               if (isspace(plus.ptr[i]))
+                       plus.ptr[i] = '\n';
+       diff_words->plus.current = 0;
+
+       xpp.flags = XDF_NEED_MINIMAL;
+       xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
+       xecfg.flags = 0;
+       ecb.outf = xdiff_outf;
+       ecb.priv = diff_words;
+       diff_words->xm.consume = fn_out_diff_words_aux;
+       xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
+
+       free(minus.ptr);
+       free(plus.ptr);
+       diff_words->minus.text.size = diff_words->plus.text.size = 0;
+
+       if (diff_words->minus.suppressed_newline) {
+               putchar('\n');
+               diff_words->minus.suppressed_newline = 0;
+       }
+}
+
 struct emit_callback {
+       struct xdiff_emit_state xm;
+       int nparents, color_diff;
        const char **label_path;
+       struct diff_words_data *diff_words;
 };
 
-static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
+static void free_diff_words_data(struct emit_callback *ecbdata)
+{
+       if (ecbdata->diff_words) {
+               /* flush buffers */
+               if (ecbdata->diff_words->minus.text.size ||
+                               ecbdata->diff_words->plus.text.size)
+                       diff_words_show(ecbdata->diff_words);
+
+               if (ecbdata->diff_words->minus.text.ptr)
+                       free (ecbdata->diff_words->minus.text.ptr);
+               if (ecbdata->diff_words->plus.text.ptr)
+                       free (ecbdata->diff_words->plus.text.ptr);
+               free(ecbdata->diff_words);
+               ecbdata->diff_words = NULL;
+       }
+}
+
+const char *diff_get_color(int diff_use_color, enum color_diff ix)
+{
+       if (diff_use_color)
+               return diff_colors[ix];
+       return "";
+}
+
+static void emit_line(const char *set, const char *reset, const char *line, int len)
+{
+       if (len > 0 && line[len-1] == '\n')
+               len--;
+       fputs(set, stdout);
+       fwrite(line, len, 1, stdout);
+       puts(reset);
+}
+
+static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
 {
+       int col0 = ecbdata->nparents;
+       int last_tab_in_indent = -1;
+       int last_space_in_indent = -1;
        int i;
+       int tail = len;
+       int need_highlight_leading_space = 0;
+       const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
+       const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
+
+       if (!*ws) {
+               emit_line(set, reset, line, len);
+               return;
+       }
+
+       /* The line is a newly added line.  Does it have funny leading
+        * whitespaces?  In indent, SP should never precede a TAB.
+        */
+       for (i = col0; i < len; i++) {
+               if (line[i] == '\t') {
+                       last_tab_in_indent = i;
+                       if (0 <= last_space_in_indent)
+                               need_highlight_leading_space = 1;
+               }
+               else if (line[i] == ' ')
+                       last_space_in_indent = i;
+               else
+                       break;
+       }
+       fputs(set, stdout);
+       fwrite(line, col0, 1, stdout);
+       fputs(reset, stdout);
+       if (((i == len) || line[i] == '\n') && i != col0) {
+               /* The whole line was indent */
+               emit_line(ws, reset, line + col0, len - col0);
+               return;
+       }
+       i = col0;
+       if (need_highlight_leading_space) {
+               while (i < last_tab_in_indent) {
+                       if (line[i] == ' ') {
+                               fputs(ws, stdout);
+                               putchar(' ');
+                               fputs(reset, stdout);
+                       }
+                       else
+                               putchar(line[i]);
+                       i++;
+               }
+       }
+       tail = len - 1;
+       if (line[tail] == '\n' && i < tail)
+               tail--;
+       while (i < tail) {
+               if (!isspace(line[tail]))
+                       break;
+               tail--;
+       }
+       if ((i < tail && line[tail + 1] != '\n')) {
+               /* This has whitespace between tail+1..len */
+               fputs(set, stdout);
+               fwrite(line + i, tail - i + 1, 1, stdout);
+               fputs(reset, stdout);
+               emit_line(ws, reset, line + tail + 1, len - tail - 1);
+       }
+       else
+               emit_line(set, reset, line + i, len - i);
+}
+
+static void fn_out_consume(void *priv, char *line, unsigned long len)
+{
+       int i;
+       int color;
        struct emit_callback *ecbdata = priv;
+       const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
+       const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
 
        if (ecbdata->label_path[0]) {
-               printf("--- %s\n", ecbdata->label_path[0]);
-               printf("+++ %s\n", ecbdata->label_path[1]);
+               printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
+               printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
        }
-       for (i = 0; i < nbuf; i++)
-               if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
-                       return -1;
-       return 0;
+
+       /* This is not really necessary for now because
+        * this codepath only deals with two-way diffs.
+        */
+       for (i = 0; i < len && line[i] == '@'; i++)
+               ;
+       if (2 <= i && i < len && line[i] == ' ') {
+               ecbdata->nparents = i - 1;
+               emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
+                         reset, line, len);
+               return;
+       }
+
+       if (len < ecbdata->nparents) {
+               set = reset;
+               emit_line(reset, reset, line, len);
+               return;
+       }
+
+       color = DIFF_PLAIN;
+       if (ecbdata->diff_words && ecbdata->nparents != 1)
+               /* fall back to normal diff */
+               free_diff_words_data(ecbdata);
+       if (ecbdata->diff_words) {
+               if (line[0] == '-') {
+                       diff_words_append(line, len,
+                                         &ecbdata->diff_words->minus);
+                       return;
+               } else if (line[0] == '+') {
+                       diff_words_append(line, len,
+                                         &ecbdata->diff_words->plus);
+                       return;
+               }
+               if (ecbdata->diff_words->minus.text.size ||
+                   ecbdata->diff_words->plus.text.size)
+                       diff_words_show(ecbdata->diff_words);
+               line++;
+               len--;
+               emit_line(set, reset, line, len);
+               return;
+       }
+       for (i = 0; i < ecbdata->nparents && len; i++) {
+               if (line[i] == '-')
+                       color = DIFF_FILE_OLD;
+               else if (line[i] == '+')
+                       color = DIFF_FILE_NEW;
+       }
+
+       if (color != DIFF_FILE_NEW) {
+               emit_line(diff_get_color(ecbdata->color_diff, color),
+                         reset, line, len);
+               return;
+       }
+       emit_add_line(reset, ecbdata, line, len);
+}
+
+static char *pprint_rename(const char *a, const char *b)
+{
+       const char *old = a;
+       const char *new = b;
+       char *name = NULL;
+       int pfx_length, sfx_length;
+       int len_a = strlen(a);
+       int len_b = strlen(b);
+
+       /* Find common prefix */
+       pfx_length = 0;
+       while (*old && *new && *old == *new) {
+               if (*old == '/')
+                       pfx_length = old - a + 1;
+               old++;
+               new++;
+       }
+
+       /* Find common suffix */
+       old = a + len_a;
+       new = b + len_b;
+       sfx_length = 0;
+       while (a <= old && b <= new && *old == *new) {
+               if (*old == '/')
+                       sfx_length = len_a - (old - a);
+               old--;
+               new--;
+       }
+
+       /*
+        * pfx{mid-a => mid-b}sfx
+        * {pfx-a => pfx-b}sfx
+        * pfx{sfx-a => sfx-b}
+        * name-a => name-b
+        */
+       if (pfx_length + sfx_length) {
+               int a_midlen = len_a - pfx_length - sfx_length;
+               int b_midlen = len_b - pfx_length - sfx_length;
+               if (a_midlen < 0) a_midlen = 0;
+               if (b_midlen < 0) b_midlen = 0;
+
+               name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
+               sprintf(name, "%.*s{%.*s => %.*s}%s",
+                       pfx_length, a,
+                       a_midlen, a + pfx_length,
+                       b_midlen, b + pfx_length,
+                       a + len_a - sfx_length);
+       }
+       else {
+               name = xmalloc(len_a + len_b + 5);
+               sprintf(name, "%s => %s", a, b);
+       }
+       return name;
 }
 
 struct diffstat_t {
@@ -202,12 +599,16 @@ struct diffstat_t {
        int alloc;
        struct diffstat_file {
                char *name;
+               unsigned is_unmerged:1;
+               unsigned is_binary:1;
+               unsigned is_renamed:1;
                unsigned int added, deleted;
        } **files;
 };
 
 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
-               const char *name)
+                                         const char *name_a,
+                                         const char *name_b)
 {
        struct diffstat_file *x;
        x = xcalloc(sizeof (*x), 1);
@@ -217,7 +618,12 @@ static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
                                diffstat->alloc * sizeof(x));
        }
        diffstat->files[diffstat->nr++] = x;
-       x->name = strdup(name);
+       if (name_b) {
+               x->name = pprint_rename(name_a, name_b);
+               x->is_renamed = 1;
+       }
+       else
+               x->name = xstrdup(name_a);
        return x;
 }
 
@@ -232,98 +638,343 @@ static void diffstat_consume(void *priv, char *line, unsigned long len)
                x->deleted++;
 }
 
-static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
-static const char minuses[]= "----------------------------------------------------------------------";
+const char mime_boundary_leader[] = "------------";
+
+static int scale_linear(int it, int width, int max_change)
+{
+       /*
+        * make sure that at least one '-' is printed if there were deletions,
+        * and likewise for '+'.
+        */
+       if (max_change < 2)
+               return it;
+       return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
+}
+
+static void show_name(const char *prefix, const char *name, int len,
+                     const char *reset, const char *set)
+{
+       printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
+}
+
+static void show_graph(char ch, int cnt, const char *set, const char *reset)
+{
+       if (cnt <= 0)
+               return;
+       printf("%s", set);
+       while (cnt--)
+               putchar(ch);
+       printf("%s", reset);
+}
 
-static void show_stats(struct diffstat_t* data)
+static void show_stats(struct diffstat_t* data, struct diff_options *options)
 {
-       char *prefix = "";
        int i, len, add, del, total, adds = 0, dels = 0;
-       int max, max_change = 0, max_len = 0;
+       int max_change = 0, max_len = 0;
        int total_files = data->nr;
+       int width, name_width;
+       const char *reset, *set, *add_c, *del_c;
 
        if (data->nr == 0)
                return;
 
-       printf("---\n");
+       width = options->stat_width ? options->stat_width : 80;
+       name_width = options->stat_name_width ? options->stat_name_width : 50;
+
+       /* Sanity: give at least 5 columns to the graph,
+        * but leave at least 10 columns for the name.
+        */
+       if (width < name_width + 15) {
+               if (name_width <= 25)
+                       width = name_width + 15;
+               else
+                       name_width = width - 15;
+       }
+
+       /* Find the longest filename and max number of changes */
+       reset = diff_get_color(options->color_diff, DIFF_RESET);
+       set = diff_get_color(options->color_diff, DIFF_PLAIN);
+       add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
+       del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
 
        for (i = 0; i < data->nr; i++) {
                struct diffstat_file *file = data->files[i];
+               int change = file->added + file->deleted;
+
+               len = quote_c_style(file->name, NULL, NULL, 0);
+               if (len) {
+                       char *qname = xmalloc(len + 1);
+                       quote_c_style(file->name, qname, NULL, 0);
+                       free(file->name);
+                       file->name = qname;
+               }
 
-               if (max_change < file->added + file->deleted)
-                       max_change = file->added + file->deleted;
                len = strlen(file->name);
                if (max_len < len)
                        max_len = len;
+
+               if (file->is_binary || file->is_unmerged)
+                       continue;
+               if (max_change < change)
+                       max_change = change;
        }
 
+       /* Compute the width of the graph part;
+        * 10 is for one blank at the beginning of the line plus
+        * " | count " between the name and the graph.
+        *
+        * From here on, name_width is the width of the name area,
+        * and width is the width of the graph area.
+        */
+       name_width = (name_width < max_len) ? name_width : max_len;
+       if (width < (name_width + 10) + max_change)
+               width = width - (name_width + 10);
+       else
+               width = max_change;
+
        for (i = 0; i < data->nr; i++) {
+               const char *prefix = "";
                char *name = data->files[i]->name;
                int added = data->files[i]->added;
                int deleted = data->files[i]->deleted;
-
-               if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
-                       char *qname = xmalloc(len + 1);
-                       quote_c_style(name, qname, NULL, 0);
-                       free(name);
-                       data->files[i]->name = name = qname;
-               }
+               int name_len;
 
                /*
                 * "scale" the filename
                 */
-               len = strlen(name);
-               max = max_len;
-               if (max > 50)
-                       max = 50;
-               if (len > max) {
+               len = name_width;
+               name_len = strlen(name);
+               if (name_width < name_len) {
                        char *slash;
                        prefix = "...";
-                       max -= 3;
-                       name += len - max;
+                       len -= 3;
+                       name += name_len - len;
                        slash = strchr(name, '/');
                        if (slash)
                                name = slash;
                }
-               len = max;
-
-               /*
-                * scale the add/delete
-                */
-               max = max_change;
-               if (max + len > 70)
-                       max = 70 - len;
 
-               if (added < 0) {
-                       /* binary file */
-                       printf(" %s%-*s |  Bin\n", prefix, len, name);
+               if (data->files[i]->is_binary) {
+                       show_name(prefix, name, len, reset, set);
+                       printf("  Bin\n");
+                       goto free_diffstat_file;
+               }
+               else if (data->files[i]->is_unmerged) {
+                       show_name(prefix, name, len, reset, set);
+                       printf("  Unmerged\n");
                        goto free_diffstat_file;
-               } else if (added + deleted == 0) {
+               }
+               else if (!data->files[i]->is_renamed &&
+                        (added + deleted == 0)) {
                        total_files--;
                        goto free_diffstat_file;
                }
 
+               /*
+                * scale the add/delete
+                */
                add = added;
                del = deleted;
                total = add + del;
                adds += add;
                dels += del;
 
-               if (max_change > 0) {
-                       total = (total * max + max_change / 2) / max_change;
-                       add = (add * max + max_change / 2) / max_change;
-                       del = total - add;
+               if (width <= max_change) {
+                       add = scale_linear(add, width, max_change);
+                       del = scale_linear(del, width, max_change);
+                       total = add + del;
                }
-               printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
-                               len, name, added + deleted,
-                               add, pluses, del, minuses);
+               show_name(prefix, name, len, reset, set);
+               printf("%5d ", added + deleted);
+               show_graph('+', add, add_c, reset);
+               show_graph('-', del, del_c, reset);
+               putchar('\n');
        free_diffstat_file:
                free(data->files[i]->name);
                free(data->files[i]);
        }
        free(data->files);
+       printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
+              set, total_files, adds, dels, reset);
+}
+
+static void show_shortstats(struct diffstat_t* data)
+{
+       int i, adds = 0, dels = 0, total_files = data->nr;
+
+       if (data->nr == 0)
+               return;
+
+       for (i = 0; i < data->nr; i++) {
+               if (!data->files[i]->is_binary &&
+                   !data->files[i]->is_unmerged) {
+                       int added = data->files[i]->added;
+                       int deleted= data->files[i]->deleted;
+                       if (!data->files[i]->is_renamed &&
+                           (added + deleted == 0)) {
+                               total_files--;
+                       } else {
+                               adds += added;
+                               dels += deleted;
+                       }
+               }
+               free(data->files[i]->name);
+               free(data->files[i]);
+       }
+       free(data->files);
+
        printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
-                       total_files, adds, dels);
+              total_files, adds, dels);
+}
+
+static void show_numstat(struct diffstat_t* data, struct diff_options *options)
+{
+       int i;
+
+       for (i = 0; i < data->nr; i++) {
+               struct diffstat_file *file = data->files[i];
+
+               if (file->is_binary)
+                       printf("-\t-\t");
+               else
+                       printf("%d\t%d\t", file->added, file->deleted);
+               if (options->line_termination &&
+                   quote_c_style(file->name, NULL, NULL, 0))
+                       quote_c_style(file->name, NULL, stdout, 0);
+               else
+                       fputs(file->name, stdout);
+               putchar(options->line_termination);
+       }
+}
+
+struct checkdiff_t {
+       struct xdiff_emit_state xm;
+       const char *filename;
+       int lineno;
+};
+
+static void checkdiff_consume(void *priv, char *line, unsigned long len)
+{
+       struct checkdiff_t *data = priv;
+
+       if (line[0] == '+') {
+               int i, spaces = 0;
+
+               /* check space before tab */
+               for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
+                       if (line[i] == ' ')
+                               spaces++;
+               if (line[i - 1] == '\t' && spaces)
+                       printf("%s:%d: space before tab:%.*s\n",
+                               data->filename, data->lineno, (int)len, line);
+
+               /* check white space at line end */
+               if (line[len - 1] == '\n')
+                       len--;
+               if (isspace(line[len - 1]))
+                       printf("%s:%d: white space at end: %.*s\n",
+                               data->filename, data->lineno, (int)len, line);
+
+               data->lineno++;
+       } else if (line[0] == ' ')
+               data->lineno++;
+       else if (line[0] == '@') {
+               char *plus = strchr(line, '+');
+               if (plus)
+                       data->lineno = strtol(plus, NULL, 10);
+               else
+                       die("invalid diff");
+       }
+}
+
+static unsigned char *deflate_it(char *data,
+                                unsigned long size,
+                                unsigned long *result_size)
+{
+       int bound;
+       unsigned char *deflated;
+       z_stream stream;
+
+       memset(&stream, 0, sizeof(stream));
+       deflateInit(&stream, zlib_compression_level);
+       bound = deflateBound(&stream, size);
+       deflated = xmalloc(bound);
+       stream.next_out = deflated;
+       stream.avail_out = bound;
+
+       stream.next_in = (unsigned char *)data;
+       stream.avail_in = size;
+       while (deflate(&stream, Z_FINISH) == Z_OK)
+               ; /* nothing */
+       deflateEnd(&stream);
+       *result_size = stream.total_out;
+       return deflated;
+}
+
+static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
+{
+       void *cp;
+       void *delta;
+       void *deflated;
+       void *data;
+       unsigned long orig_size;
+       unsigned long delta_size;
+       unsigned long deflate_size;
+       unsigned long data_size;
+
+       /* We could do deflated delta, or we could do just deflated two,
+        * whichever is smaller.
+        */
+       delta = NULL;
+       deflated = deflate_it(two->ptr, two->size, &deflate_size);
+       if (one->size && two->size) {
+               delta = diff_delta(one->ptr, one->size,
+                                  two->ptr, two->size,
+                                  &delta_size, deflate_size);
+               if (delta) {
+                       void *to_free = delta;
+                       orig_size = delta_size;
+                       delta = deflate_it(delta, delta_size, &delta_size);
+                       free(to_free);
+               }
+       }
+
+       if (delta && delta_size < deflate_size) {
+               printf("delta %lu\n", orig_size);
+               free(deflated);
+               data = delta;
+               data_size = delta_size;
+       }
+       else {
+               printf("literal %lu\n", two->size);
+               free(delta);
+               data = deflated;
+               data_size = deflate_size;
+       }
+
+       /* emit data encoded in base85 */
+       cp = data;
+       while (data_size) {
+               int bytes = (52 < data_size) ? 52 : data_size;
+               char line[70];
+               data_size -= bytes;
+               if (bytes <= 26)
+                       line[0] = bytes + 'A' - 1;
+               else
+                       line[0] = bytes - 26 + 'a' - 1;
+               encode_85(line + 1, cp, bytes);
+               cp = (char *) cp + bytes;
+               puts(line);
+       }
+       printf("\n");
+       free(data);
+}
+
+static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
+{
+       printf("GIT binary patch\n");
+       emit_binary_diff_body(one, two);
+       emit_binary_diff_body(two, one);
 }
 
 #define FIRST_FEW_BYTES 8000
@@ -332,9 +983,7 @@ static int mmfile_is_binary(mmfile_t *mf)
        long sz = mf->size;
        if (FIRST_FEW_BYTES < sz)
                sz = FIRST_FEW_BYTES;
-       if (memchr(mf->ptr, 0, sz))
-               return 1;
-       return 0;
+       return !!memchr(mf->ptr, 0, sz);
 }
 
 static void builtin_diff(const char *name_a,
@@ -342,35 +991,38 @@ static void builtin_diff(const char *name_a,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
                         const char *xfrm_msg,
+                        struct diff_options *o,
                         int complete_rewrite)
 {
        mmfile_t mf1, mf2;
        const char *lbl[2];
        char *a_one, *b_two;
+       const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
+       const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
 
        a_one = quote_two("a/", name_a);
        b_two = quote_two("b/", name_b);
        lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
        lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
-       printf("diff --git %s %s\n", a_one, b_two);
+       printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
        if (lbl[0][0] == '/') {
                /* /dev/null */
-               printf("new file mode %06o\n", two->mode);
+               printf("%snew file mode %06o%s\n", set, two->mode, reset);
                if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
+                       printf("%s%s%s\n", set, xfrm_msg, reset);
        }
        else if (lbl[1][0] == '/') {
-               printf("deleted file mode %06o\n", one->mode);
+               printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
                if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
+                       printf("%s%s%s\n", set, xfrm_msg, reset);
        }
        else {
                if (one->mode != two->mode) {
-                       printf("old mode %06o\n", one->mode);
-                       printf("new mode %06o\n", two->mode);
+                       printf("%sold mode %06o%s\n", set, one->mode, reset);
+                       printf("%snew mode %06o%s\n", set, two->mode, reset);
                }
                if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
+                       printf("%s%s%s\n", set, xfrm_msg, reset);
                /*
                 * we do not run diff between different kind
                 * of objects.
@@ -386,8 +1038,17 @@ static void builtin_diff(const char *name_a,
        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
                die("unable to read files to diff");
 
-       if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
-               printf("Binary files %s and %s differ\n", lbl[0], lbl[1]);
+       if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
+               /* Quite common confusing case */
+               if (mf1.size == mf2.size &&
+                   !memcmp(mf1.ptr, mf2.ptr, mf1.size))
+                       goto free_ab_and_return;
+               if (o->binary)
+                       emit_binary_diff(&mf1, &mf2);
+               else
+                       printf("Binary files %s and %s differ\n",
+                              lbl[0], lbl[1]);
+       }
        else {
                /* Crazy xdl interfaces.. */
                const char *diffopts = getenv("GIT_DIFF_OPTS");
@@ -396,9 +1057,11 @@ static void builtin_diff(const char *name_a,
                xdemitcb_t ecb;
                struct emit_callback ecbdata;
 
+               memset(&ecbdata, 0, sizeof(ecbdata));
                ecbdata.label_path = lbl;
-               xpp.flags = XDF_NEED_MINIMAL;
-               xecfg.ctxlen = 3;
+               ecbdata.color_diff = o->color_diff;
+               xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
+               xecfg.ctxlen = o->context;
                xecfg.flags = XDL_EMIT_FUNCNAMES;
                if (!diffopts)
                        ;
@@ -406,9 +1069,15 @@ static void builtin_diff(const char *name_a,
                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
                else if (!strncmp(diffopts, "-u", 2))
                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-               ecb.outf = fn_out;
+               ecb.outf = xdiff_outf;
                ecb.priv = &ecbdata;
+               ecbdata.xm.consume = fn_out_consume;
+               if (o->color_diff_words)
+                       ecbdata.diff_words =
+                               xcalloc(1, sizeof(struct diff_words_data));
                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
+               if (o->color_diff_words)
+                       free_diff_words_data(&ecbdata);
        }
 
  free_ab_and_return:
@@ -418,34 +1087,83 @@ static void builtin_diff(const char *name_a,
 }
 
 static void builtin_diffstat(const char *name_a, const char *name_b,
-               struct diff_filespec *one, struct diff_filespec *two,
-               struct diffstat_t *diffstat)
+                            struct diff_filespec *one,
+                            struct diff_filespec *two,
+                            struct diffstat_t *diffstat,
+                            struct diff_options *o,
+                            int complete_rewrite)
 {
        mmfile_t mf1, mf2;
        struct diffstat_file *data;
 
-       data = diffstat_add(diffstat, name_a ? name_a : name_b);
+       data = diffstat_add(diffstat, name_a, name_b);
 
+       if (!one || !two) {
+               data->is_unmerged = 1;
+               return;
+       }
+       if (complete_rewrite) {
+               diff_populate_filespec(one, 0);
+               diff_populate_filespec(two, 0);
+               data->deleted = count_lines(one->data, one->size);
+               data->added = count_lines(two->data, two->size);
+               return;
+       }
        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
                die("unable to read files to diff");
 
        if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
-               data->added = -1;
+               data->is_binary = 1;
        else {
                /* Crazy xdl interfaces.. */
                xpparam_t xpp;
                xdemitconf_t xecfg;
                xdemitcb_t ecb;
 
-               xpp.flags = XDF_NEED_MINIMAL;
-               xecfg.ctxlen = 3;
-               xecfg.flags = XDL_EMIT_FUNCNAMES;
+               xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
+               xecfg.ctxlen = 0;
+               xecfg.flags = 0;
                ecb.outf = xdiff_outf;
                ecb.priv = diffstat;
                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
        }
 }
 
+static void builtin_checkdiff(const char *name_a, const char *name_b,
+                            struct diff_filespec *one,
+                            struct diff_filespec *two)
+{
+       mmfile_t mf1, mf2;
+       struct checkdiff_t data;
+
+       if (!two)
+               return;
+
+       memset(&data, 0, sizeof(data));
+       data.xm.consume = checkdiff_consume;
+       data.filename = name_b ? name_b : name_a;
+       data.lineno = 0;
+
+       if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
+               die("unable to read files to diff");
+
+       if (mmfile_is_binary(&mf2))
+               return;
+       else {
+               /* Crazy xdl interfaces.. */
+               xpparam_t xpp;
+               xdemitconf_t xecfg;
+               xdemitcb_t ecb;
+
+               xpp.flags = XDF_NEED_MINIMAL;
+               xecfg.ctxlen = 0;
+               xecfg.flags = 0;
+               ecb.outf = xdiff_outf;
+               ecb.priv = &data;
+               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
+       }
+}
+
 struct diff_filespec *alloc_filespec(const char *path)
 {
        int namelen = strlen(path);
@@ -462,8 +1180,8 @@ void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
 {
        if (mode) {
                spec->mode = canon_mode(mode);
-               memcpy(spec->sha1, sha1, 20);
-               spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
+               hashcpy(spec->sha1, sha1);
+               spec->sha1_valid = !is_null_sha1(sha1);
        }
 }
 
@@ -472,7 +1190,7 @@ void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
  * the work tree has that object contents, return true, so that
  * prepare_temp_file() does not have to inflate and extract.
  */
-static int work_tree_matches(const char *name, const unsigned char *sha1)
+static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
 {
        struct cache_entry *ce;
        struct stat st;
@@ -493,6 +1211,18 @@ static int work_tree_matches(const char *name, const unsigned char *sha1)
        if (!active_cache)
                return 0;
 
+       /* We want to avoid the working directory if our caller
+        * doesn't need the data in a normal file, this system
+        * is rather slow with its stat/open/mmap/close syscalls,
+        * and the object is contained in a pack file.  The pack
+        * is probably already open and will be faster to obtain
+        * the data through than the working directory.  Loose
+        * objects however would tend to be slower as they need
+        * to be individually opened and inflated.
+        */
+       if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
+               return 0;
+
        len = strlen(name);
        pos = cache_name_pos(name, len);
        if (pos < 0)
@@ -501,7 +1231,7 @@ static int work_tree_matches(const char *name, const unsigned char *sha1)
        if ((lstat(name, &st) < 0) ||
            !S_ISREG(st.st_mode) || /* careful! */
            ce_match_stat(ce, &st, 0) ||
-           memcmp(sha1, ce->sha1, 20))
+           hashcmp(sha1, ce->sha1))
                return 0;
        /* we return 1 only when we can stat, it is a regular file,
         * stat information matches, and sha1 recorded in the cache
@@ -529,7 +1259,7 @@ static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
        while (last > first) {
                int cmp, next = (last + first) >> 1;
                e = sha1_size_cache[next];
-               cmp = memcmp(e->sha1, sha1, 20);
+               cmp = hashcmp(e->sha1, sha1);
                if (!cmp)
                        return e;
                if (cmp < 0) {
@@ -555,7 +1285,7 @@ static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
                        sizeof(*sha1_size_cache));
        e = xmalloc(sizeof(struct sha1_size_cache));
        sha1_size_cache[first] = e;
-       memcpy(e->sha1, sha1, 20);
+       hashcpy(e->sha1, sha1);
        e->size = size;
        return e;
 }
@@ -579,7 +1309,7 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
        if (s->data)
                return err;
        if (!s->sha1_valid ||
-           work_tree_matches(s->path, s->sha1)) {
+           reuse_worktree_file(s->path, s->sha1, 0)) {
                struct stat st;
                int fd;
                if (lstat(s->path, &st) < 0) {
@@ -587,7 +1317,7 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
                        err_empty:
                                err = -1;
                        empty:
-                               s->data = "";
+                               s->data = (char *)"";
                                s->size = 0;
                                return err;
                        }
@@ -611,10 +1341,8 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
                fd = open(s->path, O_RDONLY);
                if (fd < 0)
                        goto err_empty;
-               s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
+               s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
                close(fd);
-               if (s->data == MAP_FAILED)
-                       goto err_empty;
                s->should_munmap = 1;
        }
        else {
@@ -661,7 +1389,7 @@ static void prep_temp_blob(struct diff_tempfile *temp,
        fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
        if (fd < 0)
                die("unable to create temp-file");
-       if (write(fd, blob, size) != size)
+       if (write_in_full(fd, blob, size) != size)
                die("unable to write temp-file");
        close(fd);
        temp->name = temp->tmp_path;
@@ -686,7 +1414,7 @@ static void prepare_temp_file(const char *name,
        }
 
        if (!one->sha1_valid ||
-           work_tree_matches(name, one->sha1)) {
+           reuse_worktree_file(name, one->sha1, 1)) {
                struct stat st;
                if (lstat(name, &st) < 0) {
                        if (errno == ENOENT)
@@ -850,6 +1578,7 @@ static void run_diff_cmd(const char *pgm,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
                         const char *xfrm_msg,
+                        struct diff_options *o,
                         int complete_rewrite)
 {
        if (pgm) {
@@ -859,7 +1588,7 @@ static void run_diff_cmd(const char *pgm,
        }
        if (one && two)
                builtin_diff(name, other ? other : name,
-                            one, two, xfrm_msg, complete_rewrite);
+                            one, two, xfrm_msg, o, complete_rewrite);
        else
                printf("* Unmerged path %s\n", name);
 }
@@ -876,7 +1605,7 @@ static void diff_fill_sha1_info(struct diff_filespec *one)
                }
        }
        else
-               memset(one->sha1, 0, 20);
+               hashclr(one->sha1);
 }
 
 static void run_diff(struct diff_filepair *p, struct diff_options *o)
@@ -893,7 +1622,7 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
        if (DIFF_PAIR_UNMERGED(p)) {
                /* unmerged */
-               run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
+               run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
                return;
        }
 
@@ -939,15 +1668,19 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
                ;
        }
 
-       if (memcmp(one->sha1, two->sha1, 20)) {
-               char one_sha1[41];
+       if (hashcmp(one->sha1, two->sha1)) {
                int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
-               memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 
+               if (o->binary) {
+                       mmfile_t mf;
+                       if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
+                           (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
+                               abbrev = 40;
+               }
                len += snprintf(msg + len, sizeof(msg) - len,
                                "index %.*s..%.*s",
-                               abbrev, one_sha1, abbrev,
-                               sha1_to_hex(two->sha1));
+                               abbrev, sha1_to_hex(one->sha1),
+                               abbrev, sha1_to_hex(two->sha1));
                if (one->mode == two->mode)
                        len += snprintf(msg + len, sizeof(msg) - len,
                                        " %06o", one->mode);
@@ -965,14 +1698,14 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
                 * needs to be split into deletion and creation.
                 */
                struct diff_filespec *null = alloc_filespec(two->path);
-               run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
+               run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
                free(null);
                null = alloc_filespec(one->path);
-               run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
+               run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
                free(null);
        }
        else
-               run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
+               run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
                             complete_rewrite);
 
        free(name_munged);
@@ -980,14 +1713,36 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 }
 
 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
-               struct diffstat_t *diffstat)
+                        struct diffstat_t *diffstat)
+{
+       const char *name;
+       const char *other;
+       int complete_rewrite = 0;
+
+       if (DIFF_PAIR_UNMERGED(p)) {
+               /* unmerged */
+               builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
+               return;
+       }
+
+       name = p->one->path;
+       other = (strcmp(name, p->two->path) ? p->two->path : NULL);
+
+       diff_fill_sha1_info(p->one);
+       diff_fill_sha1_info(p->two);
+
+       if (p->status == DIFF_STATUS_MODIFIED && p->score)
+               complete_rewrite = 1;
+       builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
+}
+
+static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
 {
        const char *name;
        const char *other;
 
        if (DIFF_PAIR_UNMERGED(p)) {
                /* unmerged */
-               builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat);
                return;
        }
 
@@ -997,27 +1752,70 @@ static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
        diff_fill_sha1_info(p->one);
        diff_fill_sha1_info(p->two);
 
-       builtin_diffstat(name, other, p->one, p->two, diffstat);
+       builtin_checkdiff(name, other, p->one, p->two);
 }
 
 void diff_setup(struct diff_options *options)
 {
        memset(options, 0, sizeof(*options));
-       options->output_format = DIFF_FORMAT_RAW;
        options->line_termination = '\n';
        options->break_opt = -1;
        options->rename_limit = -1;
+       options->context = 3;
+       options->msg_sep = "";
 
        options->change = diff_change;
        options->add_remove = diff_addremove;
+       options->color_diff = diff_use_color_default;
+       options->detect_rename = diff_detect_rename_default;
 }
 
 int diff_setup_done(struct diff_options *options)
 {
-       if ((options->find_copies_harder &&
-            options->detect_rename != DIFF_DETECT_COPY) ||
-           (0 <= options->rename_limit && !options->detect_rename))
-               return -1;
+       int count = 0;
+
+       if (options->output_format & DIFF_FORMAT_NAME)
+               count++;
+       if (options->output_format & DIFF_FORMAT_NAME_STATUS)
+               count++;
+       if (options->output_format & DIFF_FORMAT_CHECKDIFF)
+               count++;
+       if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
+               count++;
+       if (count > 1)
+               die("--name-only, --name-status, --check and -s are mutually exclusive");
+
+       if (options->find_copies_harder)
+               options->detect_rename = DIFF_DETECT_COPY;
+
+       if (options->output_format & (DIFF_FORMAT_NAME |
+                                     DIFF_FORMAT_NAME_STATUS |
+                                     DIFF_FORMAT_CHECKDIFF |
+                                     DIFF_FORMAT_NO_OUTPUT))
+               options->output_format &= ~(DIFF_FORMAT_RAW |
+                                           DIFF_FORMAT_NUMSTAT |
+                                           DIFF_FORMAT_DIFFSTAT |
+                                           DIFF_FORMAT_SHORTSTAT |
+                                           DIFF_FORMAT_SUMMARY |
+                                           DIFF_FORMAT_PATCH);
+
+       /*
+        * These cases always need recursive; we do not drop caller-supplied
+        * recursive bits for other formats here.
+        */
+       if (options->output_format & (DIFF_FORMAT_PATCH |
+                                     DIFF_FORMAT_NUMSTAT |
+                                     DIFF_FORMAT_DIFFSTAT |
+                                     DIFF_FORMAT_SHORTSTAT |
+                                     DIFF_FORMAT_SUMMARY |
+                                     DIFF_FORMAT_CHECKDIFF))
+               options->recursive = 1;
+       /*
+        * Also pickaxe would not work very well if you do not say recursive
+        */
+       if (options->pickaxe)
+               options->recursive = 1;
+
        if (options->detect_rename && options->rename_limit < 0)
                options->rename_limit = diff_rename_limit_default;
        if (options->setup & DIFF_SETUP_USE_CACHE) {
@@ -1038,33 +1836,129 @@ int diff_setup_done(struct diff_options *options)
        return 0;
 }
 
+static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
+{
+       char c, *eq;
+       int len;
+
+       if (*arg != '-')
+               return 0;
+       c = *++arg;
+       if (!c)
+               return 0;
+       if (c == arg_short) {
+               c = *++arg;
+               if (!c)
+                       return 1;
+               if (val && isdigit(c)) {
+                       char *end;
+                       int n = strtoul(arg, &end, 10);
+                       if (*end)
+                               return 0;
+                       *val = n;
+                       return 1;
+               }
+               return 0;
+       }
+       if (c != '-')
+               return 0;
+       arg++;
+       eq = strchr(arg, '=');
+       if (eq)
+               len = eq - arg;
+       else
+               len = strlen(arg);
+       if (!len || strncmp(arg, arg_long, len))
+               return 0;
+       if (eq) {
+               int n;
+               char *end;
+               if (!isdigit(*++eq))
+                       return 0;
+               n = strtoul(eq, &end, 10);
+               if (*end)
+                       return 0;
+               *val = n;
+       }
+       return 1;
+}
+
 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 {
        const char *arg = av[0];
        if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
-               options->output_format = DIFF_FORMAT_PATCH;
+               options->output_format |= DIFF_FORMAT_PATCH;
+       else if (opt_arg(arg, 'U', "unified", &options->context))
+               options->output_format |= DIFF_FORMAT_PATCH;
+       else if (!strcmp(arg, "--raw"))
+               options->output_format |= DIFF_FORMAT_RAW;
        else if (!strcmp(arg, "--patch-with-raw")) {
-               options->output_format = DIFF_FORMAT_PATCH;
-               options->with_raw = 1;
+               options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
+       }
+       else if (!strcmp(arg, "--numstat")) {
+               options->output_format |= DIFF_FORMAT_NUMSTAT;
+       }
+       else if (!strcmp(arg, "--shortstat")) {
+               options->output_format |= DIFF_FORMAT_SHORTSTAT;
+       }
+       else if (!strncmp(arg, "--stat", 6)) {
+               char *end;
+               int width = options->stat_width;
+               int name_width = options->stat_name_width;
+               arg += 6;
+               end = (char *)arg;
+
+               switch (*arg) {
+               case '-':
+                       if (!strncmp(arg, "-width=", 7))
+                               width = strtoul(arg + 7, &end, 10);
+                       else if (!strncmp(arg, "-name-width=", 12))
+                               name_width = strtoul(arg + 12, &end, 10);
+                       break;
+               case '=':
+                       width = strtoul(arg+1, &end, 10);
+                       if (*end == ',')
+                               name_width = strtoul(end+1, &end, 10);
+               }
+
+               /* Important! This checks all the error cases! */
+               if (*end)
+                       return 0;
+               options->output_format |= DIFF_FORMAT_DIFFSTAT;
+               options->stat_name_width = name_width;
+               options->stat_width = width;
+       }
+       else if (!strcmp(arg, "--check"))
+               options->output_format |= DIFF_FORMAT_CHECKDIFF;
+       else if (!strcmp(arg, "--summary"))
+               options->output_format |= DIFF_FORMAT_SUMMARY;
+       else if (!strcmp(arg, "--patch-with-stat")) {
+               options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
        }
-       else if (!strcmp(arg, "--stat"))
-               options->output_format = DIFF_FORMAT_DIFFSTAT;
        else if (!strcmp(arg, "-z"))
                options->line_termination = 0;
        else if (!strncmp(arg, "-l", 2))
                options->rename_limit = strtoul(arg+2, NULL, 10);
        else if (!strcmp(arg, "--full-index"))
                options->full_index = 1;
+       else if (!strcmp(arg, "--binary")) {
+               options->output_format |= DIFF_FORMAT_PATCH;
+               options->binary = 1;
+       }
+       else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
+               options->text = 1;
+       }
        else if (!strcmp(arg, "--name-only"))
-               options->output_format = DIFF_FORMAT_NAME;
+               options->output_format |= DIFF_FORMAT_NAME;
        else if (!strcmp(arg, "--name-status"))
-               options->output_format = DIFF_FORMAT_NAME_STATUS;
+               options->output_format |= DIFF_FORMAT_NAME_STATUS;
        else if (!strcmp(arg, "-R"))
                options->reverse_diff = 1;
        else if (!strncmp(arg, "-S", 2))
                options->pickaxe = arg + 2;
-       else if (!strcmp(arg, "-s"))
-               options->output_format = DIFF_FORMAT_NO_OUTPUT;
+       else if (!strcmp(arg, "-s")) {
+               options->output_format |= DIFF_FORMAT_NO_OUTPUT;
+       }
        else if (!strncmp(arg, "-O", 2))
                options->orderfile = arg + 2;
        else if (!strncmp(arg, "--diff-filter=", 14))
@@ -1101,6 +1995,18 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                else if (40 < options->abbrev)
                        options->abbrev = 40;
        }
+       else if (!strcmp(arg, "--color"))
+               options->color_diff = 1;
+       else if (!strcmp(arg, "--no-color"))
+               options->color_diff = 0;
+       else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
+               options->xdl_opts |= XDF_IGNORE_WHITESPACE;
+       else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
+               options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
+       else if (!strcmp(arg, "--color-words"))
+               options->color_diff = options->color_diff_words = 1;
+       else if (!strcmp(arg, "--no-renames"))
+               options->detect_rename = 0;
        else
                return 0;
        return 1;
@@ -1186,13 +2092,9 @@ struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
                                 struct diff_filespec *one,
                                 struct diff_filespec *two)
 {
-       struct diff_filepair *dp = xmalloc(sizeof(*dp));
+       struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
        dp->one = one;
        dp->two = two;
-       dp->score = 0;
-       dp->status = 0;
-       dp->source_stays = 0;
-       dp->broken_pair = 0;
        if (queue)
                diff_q(queue, dp);
        return dp;
@@ -1233,15 +2135,17 @@ const char *diff_unique_abbrev(const unsigned char *sha1, int len)
 }
 
 static void diff_flush_raw(struct diff_filepair *p,
-                          int line_termination,
-                          int inter_name_termination,
-                          struct diff_options *options,
-                          int output_format)
+                          struct diff_options *options)
 {
        int two_paths;
        char status[10];
        int abbrev = options->abbrev;
        const char *path_one, *path_two;
+       int inter_name_termination = '\t';
+       int line_termination = options->line_termination;
+
+       if (!line_termination)
+               inter_name_termination = 0;
 
        path_one = p->one->path;
        path_two = p->two->path;
@@ -1270,7 +2174,7 @@ static void diff_flush_raw(struct diff_filepair *p,
                two_paths = 0;
                break;
        }
-       if (output_format != DIFF_FORMAT_NAME_STATUS) {
+       if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
                printf(":%06o %06o %s ",
                       p->one->mode, p->two->mode,
                       diff_unique_abbrev(p->one->sha1, abbrev));
@@ -1287,16 +2191,12 @@ static void diff_flush_raw(struct diff_filepair *p,
                free((void*)path_two);
 }
 
-static void diff_flush_name(struct diff_filepair *p,
-                           int inter_name_termination,
-                           int line_termination)
+static void diff_flush_name(struct diff_filepair *p, int line_termination)
 {
        char *path = p->two->path;
 
        if (line_termination)
                path = quote_one(p->two->path);
-       else
-               path = p->two->path;
        printf("%s%c", path, line_termination);
        if (p->two->path != path)
                free(path);
@@ -1329,7 +2229,7 @@ int diff_unmodified_pair(struct diff_filepair *p)
         * dealing with a change.
         */
        if (one->sha1_valid && two->sha1_valid &&
-           !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
+           !hashcmp(one->sha1, two->sha1))
                return 1; /* no change */
        if (!one->sha1_valid && !two->sha1_valid)
                return 1; /* both look at the same file on the filesystem. */
@@ -1349,7 +2249,7 @@ static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
 }
 
 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
-               struct diffstat_t *diffstat)
+                           struct diffstat_t *diffstat)
 {
        if (diff_unmodified_pair(p))
                return;
@@ -1361,6 +2261,19 @@ static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
        run_diffstat(p, o, diffstat);
 }
 
+static void diff_flush_checkdiff(struct diff_filepair *p,
+               struct diff_options *o)
+{
+       if (diff_unmodified_pair(p))
+               return;
+
+       if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
+           (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
+               return; /* no tree diffs in patch format */
+
+       run_checkdiff(p, o);
+}
+
 int diff_queue_is_empty(void)
 {
        struct diff_queue_struct *q = &diff_queued_diff;
@@ -1455,7 +2368,7 @@ static void diff_resolve_rename_copy(void)
                        if (!p->status)
                                p->status = DIFF_STATUS_RENAMED;
                }
-               else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
+               else if (hashcmp(p->one->sha1, p->two->sha1) ||
                         p->one->mode != p->two->mode)
                        p->status = DIFF_STATUS_MODIFIED;
                else {
@@ -1470,77 +2383,346 @@ static void diff_resolve_rename_copy(void)
        diff_debug_queue("resolve-rename-copy done", q);
 }
 
-static void flush_one_pair(struct diff_filepair *p,
-                          int diff_output_format,
-                          struct diff_options *options,
-                          struct diffstat_t *diffstat)
+static int check_pair_status(struct diff_filepair *p)
 {
-       int inter_name_termination = '\t';
-       int line_termination = options->line_termination;
-       if (!line_termination)
-               inter_name_termination = 0;
-
        switch (p->status) {
        case DIFF_STATUS_UNKNOWN:
-               break;
+               return 0;
        case 0:
                die("internal error in diff-resolve-rename-copy");
-               break;
        default:
-               switch (diff_output_format) {
-               case DIFF_FORMAT_DIFFSTAT:
-                       diff_flush_stat(p, options, diffstat);
-                       break;
-               case DIFF_FORMAT_PATCH:
-                       diff_flush_patch(p, options);
-                       break;
-               case DIFF_FORMAT_RAW:
-               case DIFF_FORMAT_NAME_STATUS:
-                       diff_flush_raw(p, line_termination,
-                                      inter_name_termination,
-                                      options, diff_output_format);
-                       break;
-               case DIFF_FORMAT_NAME:
-                       diff_flush_name(p,
-                                       inter_name_termination,
-                                       line_termination);
+               return 1;
+       }
+}
+
+static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
+{
+       int fmt = opt->output_format;
+
+       if (fmt & DIFF_FORMAT_CHECKDIFF)
+               diff_flush_checkdiff(p, opt);
+       else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
+               diff_flush_raw(p, opt);
+       else if (fmt & DIFF_FORMAT_NAME)
+               diff_flush_name(p, opt->line_termination);
+}
+
+static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
+{
+       if (fs->mode)
+               printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
+       else
+               printf(" %s %s\n", newdelete, fs->path);
+}
+
+
+static void show_mode_change(struct diff_filepair *p, int show_name)
+{
+       if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
+               if (show_name)
+                       printf(" mode change %06o => %06o %s\n",
+                              p->one->mode, p->two->mode, p->two->path);
+               else
+                       printf(" mode change %06o => %06o\n",
+                              p->one->mode, p->two->mode);
+       }
+}
+
+static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
+{
+       const char *old, *new;
+
+       /* Find common prefix */
+       old = p->one->path;
+       new = p->two->path;
+       while (1) {
+               const char *slash_old, *slash_new;
+               slash_old = strchr(old, '/');
+               slash_new = strchr(new, '/');
+               if (!slash_old ||
+                   !slash_new ||
+                   slash_old - old != slash_new - new ||
+                   memcmp(old, new, slash_new - new))
                        break;
-               case DIFF_FORMAT_NO_OUTPUT:
+               old = slash_old + 1;
+               new = slash_new + 1;
+       }
+       /* p->one->path thru old is the common prefix, and old and new
+        * through the end of names are renames
+        */
+       if (old != p->one->path)
+               printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
+                      (int)(old - p->one->path), p->one->path,
+                      old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
+       else
+               printf(" %s %s => %s (%d%%)\n", renamecopy,
+                      p->one->path, p->two->path,
+                      (int)(0.5 + p->score * 100.0/MAX_SCORE));
+       show_mode_change(p, 0);
+}
+
+static void diff_summary(struct diff_filepair *p)
+{
+       switch(p->status) {
+       case DIFF_STATUS_DELETED:
+               show_file_mode_name("delete", p->one);
+               break;
+       case DIFF_STATUS_ADDED:
+               show_file_mode_name("create", p->two);
+               break;
+       case DIFF_STATUS_COPIED:
+               show_rename_copy("copy", p);
+               break;
+       case DIFF_STATUS_RENAMED:
+               show_rename_copy("rename", p);
+               break;
+       default:
+               if (p->score) {
+                       printf(" rewrite %s (%d%%)\n", p->two->path,
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE));
+                       show_mode_change(p, 0);
+               } else  show_mode_change(p, 1);
+               break;
+       }
+}
+
+struct patch_id_t {
+       struct xdiff_emit_state xm;
+       SHA_CTX *ctx;
+       int patchlen;
+};
+
+static int remove_space(char *line, int len)
+{
+       int i;
+        char *dst = line;
+        unsigned char c;
+
+        for (i = 0; i < len; i++)
+                if (!isspace((c = line[i])))
+                        *dst++ = c;
+
+        return dst - line;
+}
+
+static void patch_id_consume(void *priv, char *line, unsigned long len)
+{
+       struct patch_id_t *data = priv;
+       int new_len;
+
+       /* Ignore line numbers when computing the SHA1 of the patch */
+       if (!strncmp(line, "@@ -", 4))
+               return;
+
+       new_len = remove_space(line, len);
+
+       SHA1_Update(data->ctx, line, new_len);
+       data->patchlen += new_len;
+}
+
+/* returns 0 upon success, and writes result into sha1 */
+static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
+{
+       struct diff_queue_struct *q = &diff_queued_diff;
+       int i;
+       SHA_CTX ctx;
+       struct patch_id_t data;
+       char buffer[PATH_MAX * 4 + 20];
+
+       SHA1_Init(&ctx);
+       memset(&data, 0, sizeof(struct patch_id_t));
+       data.ctx = &ctx;
+       data.xm.consume = patch_id_consume;
+
+       for (i = 0; i < q->nr; i++) {
+               xpparam_t xpp;
+               xdemitconf_t xecfg;
+               xdemitcb_t ecb;
+               mmfile_t mf1, mf2;
+               struct diff_filepair *p = q->queue[i];
+               int len1, len2;
+
+               if (p->status == 0)
+                       return error("internal diff status error");
+               if (p->status == DIFF_STATUS_UNKNOWN)
+                       continue;
+               if (diff_unmodified_pair(p))
+                       continue;
+               if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
+                   (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
+                       continue;
+               if (DIFF_PAIR_UNMERGED(p))
+                       continue;
+
+               diff_fill_sha1_info(p->one);
+               diff_fill_sha1_info(p->two);
+               if (fill_mmfile(&mf1, p->one) < 0 ||
+                               fill_mmfile(&mf2, p->two) < 0)
+                       return error("unable to read files to diff");
+
+               /* Maybe hash p->two? into the patch id? */
+               if (mmfile_is_binary(&mf2))
+                       continue;
+
+               len1 = remove_space(p->one->path, strlen(p->one->path));
+               len2 = remove_space(p->two->path, strlen(p->two->path));
+               if (p->one->mode == 0)
+                       len1 = snprintf(buffer, sizeof(buffer),
+                                       "diff--gita/%.*sb/%.*s"
+                                       "newfilemode%06o"
+                                       "---/dev/null"
+                                       "+++b/%.*s",
+                                       len1, p->one->path,
+                                       len2, p->two->path,
+                                       p->two->mode,
+                                       len2, p->two->path);
+               else if (p->two->mode == 0)
+                       len1 = snprintf(buffer, sizeof(buffer),
+                                       "diff--gita/%.*sb/%.*s"
+                                       "deletedfilemode%06o"
+                                       "---a/%.*s"
+                                       "+++/dev/null",
+                                       len1, p->one->path,
+                                       len2, p->two->path,
+                                       p->one->mode,
+                                       len1, p->one->path);
+               else
+                       len1 = snprintf(buffer, sizeof(buffer),
+                                       "diff--gita/%.*sb/%.*s"
+                                       "---a/%.*s"
+                                       "+++b/%.*s",
+                                       len1, p->one->path,
+                                       len2, p->two->path,
+                                       len1, p->one->path,
+                                       len2, p->two->path);
+               SHA1_Update(&ctx, buffer, len1);
+
+               xpp.flags = XDF_NEED_MINIMAL;
+               xecfg.ctxlen = 3;
+               xecfg.flags = XDL_EMIT_FUNCNAMES;
+               ecb.outf = xdiff_outf;
+               ecb.priv = &data;
+               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
+       }
+
+       SHA1_Final(sha1, &ctx);
+       return 0;
+}
+
+int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
+{
+       struct diff_queue_struct *q = &diff_queued_diff;
+       int i;
+       int result = diff_get_patch_id(options, sha1);
+
+       for (i = 0; i < q->nr; i++)
+               diff_free_filepair(q->queue[i]);
+
+       free(q->queue);
+       q->queue = NULL;
+       q->nr = q->alloc = 0;
+
+       return result;
+}
+
+static int is_summary_empty(const struct diff_queue_struct *q)
+{
+       int i;
+
+       for (i = 0; i < q->nr; i++) {
+               const struct diff_filepair *p = q->queue[i];
+
+               switch (p->status) {
+               case DIFF_STATUS_DELETED:
+               case DIFF_STATUS_ADDED:
+               case DIFF_STATUS_COPIED:
+               case DIFF_STATUS_RENAMED:
+                       return 0;
+               default:
+                       if (p->score)
+                               return 0;
+                       if (p->one->mode && p->two->mode &&
+                           p->one->mode != p->two->mode)
+                               return 0;
                        break;
                }
        }
+       return 1;
 }
 
 void diff_flush(struct diff_options *options)
 {
        struct diff_queue_struct *q = &diff_queued_diff;
-       int i;
-       int diff_output_format = options->output_format;
-       struct diffstat_t *diffstat = NULL;
+       int i, output_format = options->output_format;
+       int separator = 0;
+
+       /*
+        * Order: raw, stat, summary, patch
+        * or:    name/name-status/checkdiff (other bits clear)
+        */
+       if (!q->nr)
+               goto free_queue;
 
-       if (diff_output_format == DIFF_FORMAT_DIFFSTAT) {
-               diffstat = xcalloc(sizeof (struct diffstat_t), 1);
-               diffstat->xm.consume = diffstat_consume;
+       if (output_format & (DIFF_FORMAT_RAW |
+                            DIFF_FORMAT_NAME |
+                            DIFF_FORMAT_NAME_STATUS |
+                            DIFF_FORMAT_CHECKDIFF)) {
+               for (i = 0; i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+                       if (check_pair_status(p))
+                               flush_one_pair(p, options);
+               }
+               separator++;
        }
 
-       if (options->with_raw) {
+       if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
+               struct diffstat_t diffstat;
+
+               memset(&diffstat, 0, sizeof(struct diffstat_t));
+               diffstat.xm.consume = diffstat_consume;
                for (i = 0; i < q->nr; i++) {
                        struct diff_filepair *p = q->queue[i];
-                       flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
+                       if (check_pair_status(p))
+                               diff_flush_stat(p, options, &diffstat);
                }
-               putchar(options->line_termination);
+               if (output_format & DIFF_FORMAT_NUMSTAT)
+                       show_numstat(&diffstat, options);
+               if (output_format & DIFF_FORMAT_DIFFSTAT)
+                       show_stats(&diffstat, options);
+               else if (output_format & DIFF_FORMAT_SHORTSTAT)
+                       show_shortstats(&diffstat);
+               separator++;
        }
-       for (i = 0; i < q->nr; i++) {
-               struct diff_filepair *p = q->queue[i];
-               flush_one_pair(p, diff_output_format, options, diffstat);
-               diff_free_filepair(p);
+
+       if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
+               for (i = 0; i < q->nr; i++)
+                       diff_summary(q->queue[i]);
+               separator++;
        }
 
-       if (diffstat) {
-               show_stats(diffstat);
-               free(diffstat);
+       if (output_format & DIFF_FORMAT_PATCH) {
+               if (separator) {
+                       if (options->stat_sep) {
+                               /* attach patch instead of inline */
+                               fputs(options->stat_sep, stdout);
+                       } else {
+                               putchar(options->line_termination);
+                       }
+               }
+
+               for (i = 0; i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+                       if (check_pair_status(p))
+                               diff_flush_patch(p, options);
+               }
        }
 
+       if (output_format & DIFF_FORMAT_CALLBACK)
+               options->format_callback(q, options, options->format_callback_data);
+
+       for (i = 0; i < q->nr; i++)
+               diff_free_filepair(q->queue[i]);
+free_queue:
        free(q->queue);
        q->queue = NULL;
        q->nr = q->alloc = 0;
@@ -1691,10 +2873,12 @@ void diff_change(struct diff_options *options,
 }
 
 void diff_unmerge(struct diff_options *options,
-                 const char *path)
+                 const char *path,
+                 unsigned mode, const unsigned char *sha1)
 {
        struct diff_filespec *one, *two;
        one = alloc_filespec(path);
        two = alloc_filespec(path);
-       diff_queue(&diff_queued_diff, one, two);
+       fill_filespec(one, sha1, mode);
+       diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
 }