Merge branch 'js/maint-1.6.0-exec-path-env' into maint
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index 416c5aa722afc8d10e4bc910e7b297b3eb0a2760..006aa017e28dd217d07bb2c48d932e026175f98d 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -12,6 +12,7 @@
 #include "run-command.h"
 #include "utf8.h"
 #include "userdiff.h"
+#include "sigchain.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
 #define FAST_WORKING_DIRECTORY 0
@@ -23,6 +24,7 @@ static int diff_detect_rename_default;
 static int diff_rename_limit_default = 200;
 static int diff_suppress_blank_empty;
 int diff_use_color_default = -1;
+static const char *diff_word_regex_cfg;
 static const char *external_diff_cmd_cfg;
 int diff_auto_refresh_index = 1;
 static int diff_mnemonic_prefix;
@@ -92,6 +94,8 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
        }
        if (!strcmp(var, "diff.external"))
                return git_config_string(&external_diff_cmd_cfg, var, value);
+       if (!strcmp(var, "diff.wordregex"))
+               return git_config_string(&diff_word_regex_cfg, var, value);
 
        return git_diff_basic_config(var, value, cb);
 }
@@ -167,6 +171,33 @@ static struct diff_tempfile {
        char tmp_path[PATH_MAX];
 } diff_temp[2];
 
+static struct diff_tempfile *claim_diff_tempfile(void) {
+       int i;
+       for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
+               if (!diff_temp[i].name)
+                       return diff_temp + i;
+       die("BUG: diff is failing to clean up its tempfiles");
+}
+
+static int remove_tempfile_installed;
+
+static void remove_tempfile(void)
+{
+       int i;
+       for (i = 0; i < ARRAY_SIZE(diff_temp); i++) {
+               if (diff_temp[i].name == diff_temp[i].tmp_path)
+                       unlink(diff_temp[i].name);
+               diff_temp[i].name = NULL;
+       }
+}
+
+static void remove_tempfile_on_signal(int signo)
+{
+       remove_tempfile();
+       sigchain_pop(signo);
+       raise(signo);
+}
+
 static int count_lines(const char *data, int size)
 {
        int count, ch, completely_empty = 1, nl_just_seen = 0;
@@ -321,82 +352,138 @@ static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 struct diff_words_buffer {
        mmfile_t text;
        long alloc;
-       long current; /* output pointer */
-       int suppressed_newline;
+       struct diff_words_orig {
+               const char *begin, *end;
+       } *orig;
+       int orig_nr, orig_alloc;
 };
 
 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);
-       }
+       ALLOC_GROW(buffer->text.ptr, buffer->text.size + len, buffer->alloc);
        line++;
        len--;
        memcpy(buffer->text.ptr + buffer->text.size, line, len);
        buffer->text.size += len;
+       buffer->text.ptr[buffer->text.size] = '\0';
 }
 
 struct diff_words_data {
        struct diff_words_buffer minus, plus;
+       const char *current_plus;
        FILE *file;
+       regex_t *word_regex;
 };
 
-static void print_word(FILE *file, struct diff_words_buffer *buffer, int len, int color,
-               int suppress_newline)
+static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 {
-       const char *ptr;
-       int eol = 0;
+       struct diff_words_data *diff_words = priv;
+       int minus_first, minus_len, plus_first, plus_len;
+       const char *minus_begin, *minus_end, *plus_begin, *plus_end;
 
-       if (len == 0)
+       if (line[0] != '@' || parse_hunk_header(line, len,
+                       &minus_first, &minus_len, &plus_first, &plus_len))
                return;
 
-       ptr  = buffer->text.ptr + buffer->current;
-       buffer->current += len;
+       /* POSIX requires that first be decremented by one if len == 0... */
+       if (minus_len) {
+               minus_begin = diff_words->minus.orig[minus_first].begin;
+               minus_end =
+                       diff_words->minus.orig[minus_first + minus_len - 1].end;
+       } else
+               minus_begin = minus_end =
+                       diff_words->minus.orig[minus_first].end;
 
-       if (ptr[len - 1] == '\n') {
-               eol = 1;
-               len--;
+       if (plus_len) {
+               plus_begin = diff_words->plus.orig[plus_first].begin;
+               plus_end = diff_words->plus.orig[plus_first + plus_len - 1].end;
+       } else
+               plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
+
+       if (diff_words->current_plus != plus_begin)
+               fwrite(diff_words->current_plus,
+                               plus_begin - diff_words->current_plus, 1,
+                               diff_words->file);
+       if (minus_begin != minus_end)
+               color_fwrite_lines(diff_words->file,
+                               diff_get_color(1, DIFF_FILE_OLD),
+                               minus_end - minus_begin, minus_begin);
+       if (plus_begin != plus_end)
+               color_fwrite_lines(diff_words->file,
+                               diff_get_color(1, DIFF_FILE_NEW),
+                               plus_end - plus_begin, plus_begin);
+
+       diff_words->current_plus = plus_end;
+}
+
+/* This function starts looking at *begin, and returns 0 iff a word was found. */
+static int find_word_boundaries(mmfile_t *buffer, regex_t *word_regex,
+               int *begin, int *end)
+{
+       if (word_regex && *begin < buffer->size) {
+               regmatch_t match[1];
+               if (!regexec(word_regex, buffer->ptr + *begin, 1, match, 0)) {
+                       char *p = memchr(buffer->ptr + *begin + match[0].rm_so,
+                                       '\n', match[0].rm_eo - match[0].rm_so);
+                       *end = p ? p - buffer->ptr : match[0].rm_eo + *begin;
+                       *begin += match[0].rm_so;
+                       return *begin >= *end;
+               }
+               return -1;
        }
 
-       fputs(diff_get_color(1, color), file);
-       fwrite(ptr, len, 1, file);
-       fputs(diff_get_color(1, DIFF_RESET), file);
+       /* find the next word */
+       while (*begin < buffer->size && isspace(buffer->ptr[*begin]))
+               (*begin)++;
+       if (*begin >= buffer->size)
+               return -1;
 
-       if (eol) {
-               if (suppress_newline)
-                       buffer->suppressed_newline = 1;
-               else
-                       putc('\n', file);
-       }
+       /* find the end of the word */
+       *end = *begin + 1;
+       while (*end < buffer->size && !isspace(buffer->ptr[*end]))
+               (*end)++;
+
+       return 0;
 }
 
-static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
+/*
+ * This function splits the words in buffer->text, stores the list with
+ * newline separator into out, and saves the offsets of the original words
+ * in buffer->orig.
+ */
+static void diff_words_fill(struct diff_words_buffer *buffer, mmfile_t *out,
+               regex_t *word_regex)
 {
-       struct diff_words_data *diff_words = priv;
+       int i, j;
+       long alloc = 0;
 
-       if (diff_words->minus.suppressed_newline) {
-               if (line[0] != '+')
-                       putc('\n', diff_words->file);
-               diff_words->minus.suppressed_newline = 0;
-       }
+       out->size = 0;
+       out->ptr = NULL;
 
-       len--;
-       switch (line[0]) {
-               case '-':
-                       print_word(diff_words->file,
-                                  &diff_words->minus, len, DIFF_FILE_OLD, 1);
-                       break;
-               case '+':
-                       print_word(diff_words->file,
-                                  &diff_words->plus, len, DIFF_FILE_NEW, 0);
-                       break;
-               case ' ':
-                       print_word(diff_words->file,
-                                  &diff_words->plus, len, DIFF_PLAIN, 0);
-                       diff_words->minus.current += len;
-                       break;
+       /* fake an empty "0th" word */
+       ALLOC_GROW(buffer->orig, 1, buffer->orig_alloc);
+       buffer->orig[0].begin = buffer->orig[0].end = buffer->text.ptr;
+       buffer->orig_nr = 1;
+
+       for (i = 0; i < buffer->text.size; i++) {
+               if (find_word_boundaries(&buffer->text, word_regex, &i, &j))
+                       return;
+
+               /* store original boundaries */
+               ALLOC_GROW(buffer->orig, buffer->orig_nr + 1,
+                               buffer->orig_alloc);
+               buffer->orig[buffer->orig_nr].begin = buffer->text.ptr + i;
+               buffer->orig[buffer->orig_nr].end = buffer->text.ptr + j;
+               buffer->orig_nr++;
+
+               /* store one word */
+               ALLOC_GROW(out->ptr, out->size + j - i + 1, alloc);
+               memcpy(out->ptr + out->size, buffer->text.ptr + i, j - i);
+               out->ptr[out->size + j - i] = '\n';
+               out->size += j - i + 1;
+
+               i = j - 1;
        }
 }
 
@@ -407,38 +494,36 @@ static void diff_words_show(struct diff_words_data *diff_words)
        xdemitconf_t xecfg;
        xdemitcb_t ecb;
        mmfile_t minus, plus;
-       int i;
+
+       /* special case: only removal */
+       if (!diff_words->plus.text.size) {
+               color_fwrite_lines(diff_words->file,
+                       diff_get_color(1, DIFF_FILE_OLD),
+                       diff_words->minus.text.size, diff_words->minus.text.ptr);
+               diff_words->minus.text.size = 0;
+               return;
+       }
+
+       diff_words->current_plus = diff_words->plus.text.ptr;
 
        memset(&xpp, 0, sizeof(xpp));
        memset(&xecfg, 0, sizeof(xecfg));
-       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;
-
+       diff_words_fill(&diff_words->minus, &minus, diff_words->word_regex);
+       diff_words_fill(&diff_words->plus, &plus, diff_words->word_regex);
        xpp.flags = XDF_NEED_MINIMAL;
-       xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
+       /* as only the hunk header will be parsed, we need a 0-context */
+       xecfg.ctxlen = 0;
        xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
                      &xpp, &xecfg, &ecb);
        free(minus.ptr);
        free(plus.ptr);
+       if (diff_words->current_plus != diff_words->plus.text.ptr +
+                       diff_words->plus.text.size)
+               fwrite(diff_words->current_plus,
+                       diff_words->plus.text.ptr + diff_words->plus.text.size
+                       - diff_words->current_plus, 1,
+                       diff_words->file);
        diff_words->minus.text.size = diff_words->plus.text.size = 0;
-
-       if (diff_words->minus.suppressed_newline) {
-               putc('\n', diff_words->file);
-               diff_words->minus.suppressed_newline = 0;
-       }
 }
 
 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
@@ -462,7 +547,10 @@ static void free_diff_words_data(struct emit_callback *ecbdata)
                        diff_words_show(ecbdata->diff_words);
 
                free (ecbdata->diff_words->minus.text.ptr);
+               free (ecbdata->diff_words->minus.orig);
                free (ecbdata->diff_words->plus.text.ptr);
+               free (ecbdata->diff_words->plus.orig);
+               free(ecbdata->diff_words->word_regex);
                free(ecbdata->diff_words);
                ecbdata->diff_words = NULL;
        }
@@ -1325,6 +1413,12 @@ static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespe
        return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
 }
 
+static const char *userdiff_word_regex(struct diff_filespec *one)
+{
+       diff_filespec_load_driver(one);
+       return one->driver->word_regex;
+}
+
 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
 {
        if (!options->a_prefix)
@@ -1471,6 +1565,7 @@ static void builtin_diff(const char *name_a,
                ecbdata.file = o->file;
                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
                xecfg.ctxlen = o->context;
+               xecfg.interhunkctxlen = o->interhunkcontext;
                xecfg.flags = XDL_EMIT_FUNCNAMES;
                if (pe)
                        xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
@@ -1484,6 +1579,21 @@ static void builtin_diff(const char *name_a,
                        ecbdata.diff_words =
                                xcalloc(1, sizeof(struct diff_words_data));
                        ecbdata.diff_words->file = o->file;
+                       if (!o->word_regex)
+                               o->word_regex = userdiff_word_regex(one);
+                       if (!o->word_regex)
+                               o->word_regex = userdiff_word_regex(two);
+                       if (!o->word_regex)
+                               o->word_regex = diff_word_regex_cfg;
+                       if (o->word_regex) {
+                               ecbdata.diff_words->word_regex = (regex_t *)
+                                       xmalloc(sizeof(regex_t));
+                               if (regcomp(ecbdata.diff_words->word_regex,
+                                               o->word_regex,
+                                               REG_EXTENDED | REG_NEWLINE))
+                                       die ("Invalid regular expression: %s",
+                                                       o->word_regex);
+                       }
                }
                xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
                              &xpp, &xecfg, &ecb);
@@ -1858,10 +1968,11 @@ static void prep_temp_blob(struct diff_tempfile *temp,
        sprintf(temp->mode, "%06o", mode);
 }
 
-static void prepare_temp_file(const char *name,
-                             struct diff_tempfile *temp,
-                             struct diff_filespec *one)
+static struct diff_tempfile *prepare_temp_file(const char *name,
+               struct diff_filespec *one)
 {
+       struct diff_tempfile *temp = claim_diff_tempfile();
+
        if (!DIFF_FILE_VALID(one)) {
        not_a_valid_file:
                /* A '-' entry produces this for file-2, and
@@ -1870,7 +1981,13 @@ static void prepare_temp_file(const char *name,
                temp->name = "/dev/null";
                strcpy(temp->hex, ".");
                strcpy(temp->mode, ".");
-               return;
+               return temp;
+       }
+
+       if (!remove_tempfile_installed) {
+               atexit(remove_tempfile);
+               sigchain_push_common(remove_tempfile_on_signal);
+               remove_tempfile_installed = 1;
        }
 
        if (!one->sha1_valid ||
@@ -1910,7 +2027,7 @@ static void prepare_temp_file(const char *name,
                         */
                        sprintf(temp->mode, "%06o", one->mode);
                }
-               return;
+               return temp;
        }
        else {
                if (diff_populate_filespec(one, 0))
@@ -1918,24 +2035,7 @@ static void prepare_temp_file(const char *name,
                prep_temp_blob(temp, one->data, one->size,
                               one->sha1, one->mode);
        }
-}
-
-static void remove_tempfile(void)
-{
-       int i;
-
-       for (i = 0; i < 2; i++)
-               if (diff_temp[i].name == diff_temp[i].tmp_path) {
-                       unlink(diff_temp[i].name);
-                       diff_temp[i].name = NULL;
-               }
-}
-
-static void remove_tempfile_on_signal(int signo)
-{
-       remove_tempfile();
-       signal(SIGINT, SIG_DFL);
-       raise(signo);
+       return temp;
 }
 
 /* An external diff command takes:
@@ -1953,34 +2053,22 @@ static void run_external_diff(const char *pgm,
                              int complete_rewrite)
 {
        const char *spawn_arg[10];
-       struct diff_tempfile *temp = diff_temp;
        int retval;
-       static int atexit_asked = 0;
-       const char *othername;
        const char **arg = &spawn_arg[0];
 
-       othername = (other? other : name);
-       if (one && two) {
-               prepare_temp_file(name, &temp[0], one);
-               prepare_temp_file(othername, &temp[1], two);
-               if (! atexit_asked &&
-                   (temp[0].name == temp[0].tmp_path ||
-                    temp[1].name == temp[1].tmp_path)) {
-                       atexit_asked = 1;
-                       atexit(remove_tempfile);
-               }
-               signal(SIGINT, remove_tempfile_on_signal);
-       }
-
        if (one && two) {
+               struct diff_tempfile *temp_one, *temp_two;
+               const char *othername = (other ? other : name);
+               temp_one = prepare_temp_file(name, one);
+               temp_two = prepare_temp_file(othername, two);
                *arg++ = pgm;
                *arg++ = name;
-               *arg++ = temp[0].name;
-               *arg++ = temp[0].hex;
-               *arg++ = temp[0].mode;
-               *arg++ = temp[1].name;
-               *arg++ = temp[1].hex;
-               *arg++ = temp[1].mode;
+               *arg++ = temp_one->name;
+               *arg++ = temp_one->hex;
+               *arg++ = temp_one->mode;
+               *arg++ = temp_two->name;
+               *arg++ = temp_two->hex;
+               *arg++ = temp_two->mode;
                if (other) {
                        *arg++ = other;
                        *arg++ = xfrm_msg;
@@ -2111,7 +2199,7 @@ static void diff_fill_sha1_info(struct diff_filespec *one)
                        if (lstat(one->path, &st) < 0)
                                die("stat %s", one->path);
                        if (index_path(one->sha1, one->path, &st, 0))
-                               die("cannot hash %s\n", one->path);
+                               die("cannot hash %s", one->path);
                }
        }
        else
@@ -2238,15 +2326,12 @@ void diff_setup(struct diff_options *options)
        options->break_opt = -1;
        options->rename_limit = -1;
        options->dirstat_percent = 3;
-       DIFF_OPT_CLR(options, DIRSTAT_CUMULATIVE);
        options->context = 3;
 
        options->change = diff_change;
        options->add_remove = diff_addremove;
        if (diff_use_color_default > 0)
                DIFF_OPT_SET(options, COLOR_DIFF);
-       else
-               DIFF_OPT_CLR(options, COLOR_DIFF);
        options->detect_rename = diff_detect_rename_default;
 
        if (!diff_mnemonic_prefix) {
@@ -2487,6 +2572,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
        else if (!strcmp(arg, "--ignore-space-at-eol"))
                options->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL;
+       else if (!strcmp(arg, "--patience"))
+               options->xdl_opts |= XDF_PATIENCE_DIFF;
 
        /* flags options */
        else if (!strcmp(arg, "--binary")) {
@@ -2509,6 +2596,10 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                DIFF_OPT_CLR(options, COLOR_DIFF);
        else if (!strcmp(arg, "--color-words"))
                options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
+       else if (!prefixcmp(arg, "--color-words=")) {
+               options->flags |= DIFF_OPT_COLOR_DIFF | DIFF_OPT_COLOR_DIFF_WORDS;
+               options->word_regex = arg + 14;
+       }
        else if (!strcmp(arg, "--exit-code"))
                DIFF_OPT_SET(options, EXIT_WITH_STATUS);
        else if (!strcmp(arg, "--quiet"))
@@ -2554,6 +2645,9 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->b_prefix = arg + 13;
        else if (!strcmp(arg, "--no-prefix"))
                options->a_prefix = options->b_prefix = "";
+       else if (opt_arg(arg, '\0', "inter-hunk-context",
+                        &options->interhunkcontext))
+               ;
        else if (!prefixcmp(arg, "--output=")) {
                options->file = fopen(arg + strlen("--output="), "w");
                options->close_file = 1;
@@ -3460,15 +3554,15 @@ void diff_unmerge(struct diff_options *options,
 static char *run_textconv(const char *pgm, struct diff_filespec *spec,
                size_t *outsize)
 {
-       struct diff_tempfile temp;
+       struct diff_tempfile *temp;
        const char *argv[3];
        const char **arg = argv;
        struct child_process child;
        struct strbuf buf = STRBUF_INIT;
 
-       prepare_temp_file(spec->path, &temp, spec);
+       temp = prepare_temp_file(spec->path, spec);
        *arg++ = pgm;
-       *arg++ = temp.name;
+       *arg++ = temp->name;
        *arg = NULL;
 
        memset(&child, 0, sizeof(child));
@@ -3477,13 +3571,11 @@ static char *run_textconv(const char *pgm, struct diff_filespec *spec,
        if (start_command(&child) != 0 ||
            strbuf_read(&buf, child.out, 0) < 0 ||
            finish_command(&child) != 0) {
-               if (temp.name == temp.tmp_path)
-                       unlink(temp.name);
+               remove_tempfile();
                error("error running textconv command '%s'", pgm);
                return NULL;
        }
-       if (temp.name == temp.tmp_path)
-               unlink(temp.name);
+       remove_tempfile();
 
        return strbuf_detach(&buf, outsize);
 }