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[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index b28933f870d7dd11596fd3715280e1488ac2430f..9938969fa50e8af2a4eabe96ae122111ae42fe75 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -8,6 +8,7 @@
 #include "delta.h"
 #include "xdiff-interface.h"
 #include "color.h"
+#include "attr.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
 #define FAST_WORKING_DIRECTORY 0
@@ -15,8 +16,6 @@
 #define FAST_WORKING_DIRECTORY 1
 #endif
 
-static int use_size_cache;
-
 static int diff_detect_rename_default;
 static int diff_rename_limit_default = -1;
 static int diff_use_color_default;
@@ -51,6 +50,49 @@ static int parse_diff_color_slot(const char *var, int ofs)
        die("bad config variable '%s'", var);
 }
 
+static struct ll_diff_driver {
+       const char *name;
+       struct ll_diff_driver *next;
+       char *cmd;
+} *user_diff, **user_diff_tail;
+
+/*
+ * Currently there is only "diff.<drivername>.command" variable;
+ * because there are "diff.color.<slot>" variables, we are parsing
+ * this in a bit convoluted way to allow low level diff driver
+ * called "color".
+ */
+static int parse_lldiff_command(const char *var, const char *ep, const char *value)
+{
+       const char *name;
+       int namelen;
+       struct ll_diff_driver *drv;
+
+       name = var + 5;
+       namelen = ep - name;
+       for (drv = user_diff; drv; drv = drv->next)
+               if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
+                       break;
+       if (!drv) {
+               char *namebuf;
+               drv = xcalloc(1, sizeof(struct ll_diff_driver));
+               namebuf = xmalloc(namelen + 1);
+               memcpy(namebuf, name, namelen);
+               namebuf[namelen] = 0;
+               drv->name = namebuf;
+               drv->next = NULL;
+               if (!user_diff_tail)
+                       user_diff_tail = &user_diff;
+               *user_diff_tail = drv;
+               user_diff_tail = &(drv->next);
+       }
+
+       if (!value)
+               return error("%s: lacks value", var);
+       drv->cmd = strdup(value);
+       return 0;
+}
+
 /*
  * These are to give UI layer defaults.
  * The core-level commands such as git-diff-files should
@@ -77,11 +119,18 @@ int git_diff_ui_config(const char *var, const char *value)
                        diff_detect_rename_default = DIFF_DETECT_RENAME;
                return 0;
        }
+       if (!prefixcmp(var, "diff.")) {
+               const char *ep = strrchr(var, '.');
+
+               if (ep != var + 4 && !strcmp(ep, ".command"))
+                       return parse_lldiff_command(var, ep, value);
+       }
        if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
                int slot = parse_diff_color_slot(var, 11);
                color_parse(value, var, diff_colors[slot]);
                return 0;
        }
+
        return git_default_config(var, value);
 }
 
@@ -137,13 +186,11 @@ static const char *external_diff(void)
        return external_diff_cmd;
 }
 
-#define TEMPFILE_PATH_LEN              50
-
 static struct diff_tempfile {
        const char *name; /* filename external diff should read from */
        char hex[41];
        char mode[10];
-       char tmp_path[TEMPFILE_PATH_LEN];
+       char tmp_path[PATH_MAX];
 } diff_temp[2];
 
 static int count_lines(const char *data, int size)
@@ -811,7 +858,12 @@ static void show_stats(struct diffstat_t* data, struct diff_options *options)
 
                if (data->files[i]->is_binary) {
                        show_name(prefix, name, len, reset, set);
-                       printf("  Bin\n");
+                       printf("  Bin ");
+                       printf("%s%d%s", del_c, deleted, reset);
+                       printf(" -> ");
+                       printf("%s%d%s", add_c, added, reset);
+                       printf(" bytes");
+                       printf("\n");
                        goto free_diffstat_file;
                }
                else if (data->files[i]->is_unmerged) {
@@ -1046,13 +1098,34 @@ static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
        emit_binary_diff_body(two, one);
 }
 
-#define FIRST_FEW_BYTES 8000
-static int mmfile_is_binary(mmfile_t *mf)
+static void setup_diff_attr_check(struct git_attr_check *check)
 {
-       long sz = mf->size;
-       if (FIRST_FEW_BYTES < sz)
-               sz = FIRST_FEW_BYTES;
-       return !!memchr(mf->ptr, 0, sz);
+       static struct git_attr *attr_diff;
+
+       if (!attr_diff)
+               attr_diff = git_attr("diff", 4);
+       check->attr = attr_diff;
+}
+
+static int file_is_binary(struct diff_filespec *one)
+{
+       struct git_attr_check attr_diff_check;
+
+       setup_diff_attr_check(&attr_diff_check);
+       if (!git_checkattr(one->path, 1, &attr_diff_check)) {
+               const char *value = attr_diff_check.value;
+               if (ATTR_TRUE(value))
+                       return 0;
+               else if (ATTR_FALSE(value))
+                       return 1;
+       }
+
+       if (!one->data) {
+               if (!DIFF_FILE_VALID(one))
+                       return 0;
+               diff_populate_filespec(one, 0);
+       }
+       return buffer_is_binary(one->data, one->size);
 }
 
 static void builtin_diff(const char *name_a,
@@ -1109,7 +1182,7 @@ 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 (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
+       if (!o->text && (file_is_binary(one) || file_is_binary(two))) {
                /* Quite common confusing case */
                if (mf1.size == mf2.size &&
                    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
@@ -1154,6 +1227,8 @@ static void builtin_diff(const char *name_a,
        }
 
  free_ab_and_return:
+       diff_free_filespec_data(one);
+       diff_free_filespec_data(two);
        free(a_one);
        free(b_two);
        return;
@@ -1180,14 +1255,16 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
                diff_populate_filespec(two, 0);
                data->deleted = count_lines(one->data, one->size);
                data->added = count_lines(two->data, two->size);
-               return;
+               goto free_and_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))
+       if (file_is_binary(one) || file_is_binary(two)) {
                data->is_binary = 1;
-       else {
+               data->added = mf2.size;
+               data->deleted = mf1.size;
+       } else {
                /* Crazy xdl interfaces.. */
                xpparam_t xpp;
                xdemitconf_t xecfg;
@@ -1200,6 +1277,10 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
                ecb.priv = diffstat;
                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
        }
+
+ free_and_return:
+       diff_free_filespec_data(one);
+       diff_free_filespec_data(two);
 }
 
 static void builtin_checkdiff(const char *name_a, const char *name_b,
@@ -1221,8 +1302,8 @@ static void builtin_checkdiff(const char *name_a, const char *name_b,
        if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
                die("unable to read files to diff");
 
-       if (mmfile_is_binary(&mf2))
-               return;
+       if (file_is_binary(two))
+               goto free_and_return;
        else {
                /* Crazy xdl interfaces.. */
                xpparam_t xpp;
@@ -1236,6 +1317,9 @@ static void builtin_checkdiff(const char *name_a, const char *name_b,
                ecb.priv = &data;
                xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
        }
+ free_and_return:
+       diff_free_filespec_data(one);
+       diff_free_filespec_data(two);
 }
 
 struct diff_filespec *alloc_filespec(const char *path)
@@ -1260,7 +1344,7 @@ void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
 }
 
 /*
- * Given a name and sha1 pair, if the dircache tells us the file in
+ * Given a name and sha1 pair, if the index tells us the file in
  * the work tree has that object contents, return true, so that
  * prepare_temp_file() does not have to inflate and extract.
  */
@@ -1315,61 +1399,12 @@ static int reuse_worktree_file(const char *name, const unsigned char *sha1, int
        return 1;
 }
 
-static struct sha1_size_cache {
-       unsigned char sha1[20];
-       unsigned long size;
-} **sha1_size_cache;
-static int sha1_size_cache_nr, sha1_size_cache_alloc;
-
-static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
-                                                int find_only,
-                                                unsigned long size)
-{
-       int first, last;
-       struct sha1_size_cache *e;
-
-       first = 0;
-       last = sha1_size_cache_nr;
-       while (last > first) {
-               int cmp, next = (last + first) >> 1;
-               e = sha1_size_cache[next];
-               cmp = hashcmp(e->sha1, sha1);
-               if (!cmp)
-                       return e;
-               if (cmp < 0) {
-                       last = next;
-                       continue;
-               }
-               first = next+1;
-       }
-       /* not found */
-       if (find_only)
-               return NULL;
-       /* insert to make it at "first" */
-       if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
-               sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
-               sha1_size_cache = xrealloc(sha1_size_cache,
-                                          sha1_size_cache_alloc *
-                                          sizeof(*sha1_size_cache));
-       }
-       sha1_size_cache_nr++;
-       if (first < sha1_size_cache_nr)
-               memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
-                       (sha1_size_cache_nr - first - 1) *
-                       sizeof(*sha1_size_cache));
-       e = xmalloc(sizeof(struct sha1_size_cache));
-       sha1_size_cache[first] = e;
-       hashcpy(e->sha1, sha1);
-       e->size = size;
-       return e;
-}
-
 static int populate_from_stdin(struct diff_filespec *s)
 {
 #define INCREMENT 1024
        char *buf;
        unsigned long size;
-       int got;
+       ssize_t got;
 
        size = 0;
        buf = NULL;
@@ -1390,6 +1425,22 @@ static int populate_from_stdin(struct diff_filespec *s)
        return 0;
 }
 
+static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
+{
+       int len;
+       char *data = xmalloc(100);
+       len = snprintf(data, 100,
+               "Subproject commit %s\n", sha1_to_hex(s->sha1));
+       s->data = data;
+       s->size = len;
+       s->should_free = 1;
+       if (size_only) {
+               s->data = NULL;
+               free(data);
+       }
+       return 0;
+}
+
 /*
  * While doing rename detection and pickaxe operation, we may need to
  * grab the data for the blob (or file) for our own in-core comparison.
@@ -1403,11 +1454,15 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
        if (S_ISDIR(s->mode))
                return -1;
 
-       if (!use_size_cache)
-               size_only = 0;
-
        if (s->data)
-               return err;
+               return 0;
+
+       if (size_only && 0 < s->size)
+               return 0;
+
+       if (S_ISGITLINK(s->mode))
+               return diff_populate_gitlink(s, size_only);
+
        if (!s->sha1_valid ||
            reuse_worktree_file(s->path, s->sha1, 0)) {
                struct stat st;
@@ -1454,9 +1509,9 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
                /*
                 * Convert from working tree format to canonical git format
                 */
-               buf = s->data;
                size = s->size;
-               if (convert_to_git(s->path, &buf, &size)) {
+               buf = convert_to_git(s->path, s->data, &size);
+               if (buf) {
                        munmap(s->data, s->size);
                        s->should_munmap = 0;
                        s->data = buf;
@@ -1466,19 +1521,8 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
        }
        else {
                enum object_type type;
-               struct sha1_size_cache *e;
-
-               if (size_only && use_size_cache &&
-                   (e = locate_size_cache(s->sha1, 1, 0)) != NULL) {
-                       s->size = e->size;
-                       return 0;
-               }
-
-               if (size_only) {
+               if (size_only)
                        type = sha1_object_info(s->sha1, &s->size);
-                       if (use_size_cache && 0 < type)
-                               locate_size_cache(s->sha1, 0, s->size);
-               }
                else {
                        s->data = read_sha1_file(s->sha1, &type, &s->size);
                        s->should_free = 1;
@@ -1493,8 +1537,11 @@ void diff_free_filespec_data(struct diff_filespec *s)
                free(s->data);
        else if (s->should_munmap)
                munmap(s->data, s->size);
-       s->should_free = s->should_munmap = 0;
-       s->data = NULL;
+
+       if (s->should_free || s->should_munmap) {
+               s->should_free = s->should_munmap = 0;
+               s->data = NULL;
+       }
        free(s->cnt_data);
        s->cnt_data = NULL;
 }
@@ -1507,7 +1554,7 @@ static void prep_temp_blob(struct diff_tempfile *temp,
 {
        int fd;
 
-       fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
+       fd = git_mkstemp(temp->tmp_path, PATH_MAX, ".diff_XXXXXX");
        if (fd < 0)
                die("unable to create temp-file");
        if (write_in_full(fd, blob, size) != size)
@@ -1694,6 +1741,30 @@ static void run_external_diff(const char *pgm,
        }
 }
 
+static const char *external_diff_attr(const char *name)
+{
+       struct git_attr_check attr_diff_check;
+
+       setup_diff_attr_check(&attr_diff_check);
+       if (!git_checkattr(name, 1, &attr_diff_check)) {
+               const char *value = attr_diff_check.value;
+               if (!ATTR_TRUE(value) &&
+                   !ATTR_FALSE(value) &&
+                   !ATTR_UNSET(value)) {
+                       struct ll_diff_driver *drv;
+
+                       if (!user_diff_tail) {
+                               user_diff_tail = &user_diff;
+                               git_config(git_diff_ui_config);
+                       }
+                       for (drv = user_diff; drv; drv = drv->next)
+                               if (!strcmp(drv->name, value))
+                                       return drv->cmd;
+               }
+       }
+       return NULL;
+}
+
 static void run_diff_cmd(const char *pgm,
                         const char *name,
                         const char *other,
@@ -1703,6 +1774,14 @@ static void run_diff_cmd(const char *pgm,
                         struct diff_options *o,
                         int complete_rewrite)
 {
+       if (!o->allow_external)
+               pgm = NULL;
+       else {
+               const char *cmd = external_diff_attr(name);
+               if (cmd)
+                       pgm = cmd;
+       }
+
        if (pgm) {
                run_external_diff(pgm, name, other, one, two, xfrm_msg,
                                  complete_rewrite);
@@ -1799,8 +1878,8 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
                if (o->binary) {
                        mmfile_t mf;
-                       if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
-                           (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
+                       if ((!fill_mmfile(&mf, one) && file_is_binary(one)) ||
+                           (!fill_mmfile(&mf, two) && file_is_binary(two)))
                                abbrev = 40;
                }
                len += snprintf(msg + len, sizeof(msg) - len,
@@ -1954,8 +2033,6 @@ int diff_setup_done(struct diff_options *options)
                         */
                        read_cache();
        }
-       if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
-               use_size_cache = 1;
        if (options->abbrev <= 0 || 40 < options->abbrev)
                options->abbrev = 40; /* full */
 
@@ -2026,6 +2103,8 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
        return 1;
 }
 
+static int diff_scoreopt_parse(const char *opt);
+
 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 {
        const char *arg = av[0];
@@ -2122,6 +2201,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->detect_rename = DIFF_DETECT_RENAME;
        }
        else if (!prefixcmp(arg, "-C")) {
+               if (options->detect_rename == DIFF_DETECT_COPY)
+                       options->find_copies_harder = 1;
                if ((options->rename_score =
                     diff_scoreopt_parse(arg)) == -1)
                        return -1;
@@ -2129,6 +2210,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        }
        else if (!strcmp(arg, "--find-copies-harder"))
                options->find_copies_harder = 1;
+       else if (!strcmp(arg, "--follow"))
+               options->follow_renames = 1;
        else if (!strcmp(arg, "--abbrev"))
                options->abbrev = DEFAULT_ABBREV;
        else if (!prefixcmp(arg, "--abbrev=")) {
@@ -2197,7 +2280,7 @@ static int parse_num(const char **cp_p)
        return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
 }
 
-int diff_scoreopt_parse(const char *opt)
+static int diff_scoreopt_parse(const char *opt)
 {
        int opt1, opt2, cmd;
 
@@ -2695,7 +2778,7 @@ static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
                        return error("unable to read files to diff");
 
                /* Maybe hash p->two? into the patch id? */
-               if (mmfile_is_binary(&mf2))
+               if (file_is_binary(p->two))
                        continue;
 
                len1 = remove_space(p->one->path, strlen(p->one->path));
@@ -2954,7 +3037,7 @@ void diff_addremove(struct diff_options *options,
         * entries to the diff-core.  They will be prefixed
         * with something like '=' or '*' (I haven't decided
         * which but should not make any difference).
-        * Feeding the same new and old to diff_change() 
+        * Feeding the same new and old to diff_change()
         * also has the same effect.
         * Before the final output happens, they are pruned after
         * merged into rename/copy pairs as appropriate.
@@ -2981,7 +3064,7 @@ void diff_change(struct diff_options *options,
                 unsigned old_mode, unsigned new_mode,
                 const unsigned char *old_sha1,
                 const unsigned char *new_sha1,
-                const char *base, const char *path) 
+                const char *base, const char *path)
 {
        char concatpath[PATH_MAX];
        struct diff_filespec *one, *two;