index-pack: use hash_sha1_file()
[gitweb.git] / tree-diff.c
index 382092bce0be4ac82098ccc9c19d52df80f4eafd..b2f35dc3d82a2a2ef4726073ca3f77f10c7c28bb 100644 (file)
@@ -3,43 +3,10 @@
  */
 #include "cache.h"
 #include "diff.h"
+#include "tree.h"
 
-// What paths are we interested in?
-static int nr_paths = 0;
-static const char **paths = NULL;
-static int *pathlens = NULL;
-
-static void update_tree_entry(struct tree_desc *desc)
+static char *malloc_base(const char *base, int baselen, const char *path, int pathlen)
 {
-       void *buf = desc->buf;
-       unsigned long size = desc->size;
-       int len = strlen(buf) + 1 + 20;
-
-       if (size < len)
-               die("corrupt tree file");
-       desc->buf = buf + len;
-       desc->size = size - len;
-}
-
-static const unsigned char *extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
-{
-       void *tree = desc->buf;
-       unsigned long size = desc->size;
-       int len = strlen(tree)+1;
-       const unsigned char *sha1 = tree + len;
-       const char *path = strchr(tree, ' ');
-       unsigned int mode;
-
-       if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
-               die("corrupt tree file");
-       *pathp = path+1;
-       *modep = DIFF_FILE_CANON_MODE(mode);
-       return sha1;
-}
-
-static char *malloc_base(const char *base, const char *path, int pathlen)
-{
-       int baselen = strlen(base);
        char *newbase = xmalloc(baselen + pathlen + 2);
        memcpy(newbase, base, baselen);
        memcpy(newbase + baselen, path, pathlen);
@@ -47,31 +14,31 @@ static char *malloc_base(const char *base, const char *path, int pathlen)
        return newbase;
 }
 
-static int show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base);
+static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
+                      const char *base, int baselen);
 
-static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
+static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, int baselen, struct diff_options *opt)
 {
        unsigned mode1, mode2;
        const char *path1, *path2;
        const unsigned char *sha1, *sha2;
        int cmp, pathlen1, pathlen2;
 
-       sha1 = extract(t1, &path1, &mode1);
-       sha2 = extract(t2, &path2, &mode2);
+       sha1 = tree_entry_extract(t1, &path1, &mode1);
+       sha2 = tree_entry_extract(t2, &path2, &mode2);
 
-       pathlen1 = strlen(path1);
-       pathlen2 = strlen(path2);
+       pathlen1 = tree_entry_len(path1, sha1);
+       pathlen2 = tree_entry_len(path2, sha2);
        cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
        if (cmp < 0) {
-               show_entry(opt, "-", t1, base);
+               show_entry(opt, "-", t1, base, baselen);
                return -1;
        }
        if (cmp > 0) {
-               show_entry(opt, "+", t2, base);
+               show_entry(opt, "+", t2, base, baselen);
                return 1;
        }
-       if (!opt->find_copies_harder &&
-           !memcmp(sha1, sha2, 20) && mode1 == mode2)
+       if (!opt->find_copies_harder && !hashcmp(sha1, sha2) && mode1 == mode2)
                return 0;
 
        /*
@@ -79,14 +46,14 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const
         * file, we need to consider it a remove and an add.
         */
        if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
-               show_entry(opt, "-", t1, base);
-               show_entry(opt, "+", t2, base);
+               show_entry(opt, "-", t1, base, baselen);
+               show_entry(opt, "+", t2, base, baselen);
                return 0;
        }
 
        if (opt->recursive && S_ISDIR(mode1)) {
                int retval;
-               char *newbase = malloc_base(base, path1, pathlen1);
+               char *newbase = malloc_base(base, baselen, path1, pathlen1);
                if (opt->tree_in_recursive)
                        opt->change(opt, mode1, mode2,
                                    sha1, sha2, base, path1);
@@ -99,24 +66,32 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const
        return 0;
 }
 
-static int interesting(struct tree_desc *desc, const char *base)
+/*
+ * Is a tree entry interesting given the pathspec we have?
+ *
+ * Return:
+ *  - positive for yes
+ *  - zero for no
+ *  - negative for "no, and no subsequent entries will be either"
+ */
+static int tree_entry_interesting(struct tree_desc *desc, const char *base, int baselen, struct diff_options *opt)
 {
        const char *path;
+       const unsigned char *sha1;
        unsigned mode;
        int i;
-       int baselen, pathlen;
+       int pathlen;
 
-       if (!nr_paths)
+       if (!opt->nr_paths)
                return 1;
 
-       (void)extract(desc, &path, &mode);
+       sha1 = tree_entry_extract(desc, &path, &mode);
 
-       pathlen = strlen(path);
-       baselen = strlen(base);
+       pathlen = tree_entry_len(path, sha1);
 
-       for (i=0; i < nr_paths; i++) {
-               const char *match = paths[i];
-               int matchlen = pathlens[i];
+       for (i=0; i < opt->nr_paths; i++) {
+               const char *match = opt->paths[i];
+               int matchlen = opt->pathlens[i];
 
                if (baselen >= matchlen) {
                        /* If it doesn't match, move along... */
@@ -153,66 +128,86 @@ static int interesting(struct tree_desc *desc, const char *base)
 }
 
 /* A whole sub-tree went away or appeared */
-static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base)
+static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base, int baselen)
 {
        while (desc->size) {
-               if (interesting(desc, base))
-                       show_entry(opt, prefix, desc, base);
+               int show = tree_entry_interesting(desc, base, baselen, opt);
+               if (show < 0)
+                       break;
+               if (show)
+                       show_entry(opt, prefix, desc, base, baselen);
                update_tree_entry(desc);
        }
 }
 
 /* A file entry went away or appeared */
-static int show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base)
+static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc,
+                      const char *base, int baselen)
 {
        unsigned mode;
        const char *path;
-       const unsigned char *sha1 = extract(desc, &path, &mode);
+       const unsigned char *sha1 = tree_entry_extract(desc, &path, &mode);
 
        if (opt->recursive && S_ISDIR(mode)) {
-               char type[20];
-               char *newbase = malloc_base(base, path, strlen(path));
+               enum object_type type;
+               int pathlen = tree_entry_len(path, sha1);
+               char *newbase = malloc_base(base, baselen, path, pathlen);
                struct tree_desc inner;
                void *tree;
 
-               tree = read_sha1_file(sha1, type, &inner.size);
-               if (!tree || strcmp(type, "tree"))
+               tree = read_sha1_file(sha1, &type, &inner.size);
+               if (!tree || type != OBJ_TREE)
                        die("corrupt tree sha %s", sha1_to_hex(sha1));
 
                inner.buf = tree;
-               show_tree(opt, prefix, &inner, newbase);
+               show_tree(opt, prefix, &inner, newbase, baselen + 1 + pathlen);
 
                free(tree);
                free(newbase);
-               return 0;
+       } else {
+               opt->add_remove(opt, prefix[0], mode, sha1, base, path);
        }
-
-       opt->add_remove(opt, prefix[0], mode, sha1, base, path);
-       return 0;
 }
 
-int diff_tree(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
+static void skip_uninteresting(struct tree_desc *t, const char *base, int baselen, struct diff_options *opt)
 {
-       while (t1->size | t2->size) {
-               if (nr_paths && t1->size && !interesting(t1, base)) {
-                       update_tree_entry(t1);
+       while (t->size) {
+               int show = tree_entry_interesting(t, base, baselen, opt);
+               if (!show) {
+                       update_tree_entry(t);
                        continue;
                }
-               if (nr_paths && t2->size && !interesting(t2, base)) {
-                       update_tree_entry(t2);
-                       continue;
+               /* Skip it all? */
+               if (show < 0)
+                       t->size = 0;
+               return;
+       }
+}
+
+int diff_tree(struct tree_desc *t1, struct tree_desc *t2, const char *base, struct diff_options *opt)
+{
+       int baselen = strlen(base);
+
+       for (;;) {
+               if (opt->quiet && opt->has_changes)
+                       break;
+               if (opt->nr_paths) {
+                       skip_uninteresting(t1, base, baselen, opt);
+                       skip_uninteresting(t2, base, baselen, opt);
                }
                if (!t1->size) {
-                       show_entry(opt, "+", t2, base);
+                       if (!t2->size)
+                               break;
+                       show_entry(opt, "+", t2, base, baselen);
                        update_tree_entry(t2);
                        continue;
                }
                if (!t2->size) {
-                       show_entry(opt, "-", t1, base);
+                       show_entry(opt, "-", t1, base, baselen);
                        update_tree_entry(t1);
                        continue;
                }
-               switch (compare_tree_entry(t1, t2, base, opt)) {
+               switch (compare_tree_entry(t1, t2, base, baselen, opt)) {
                case -1:
                        update_tree_entry(t1);
                        continue;
@@ -234,10 +229,10 @@ int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const cha
        struct tree_desc t1, t2;
        int retval;
 
-       tree1 = read_object_with_reference(old, "tree", &t1.size, NULL);
+       tree1 = read_object_with_reference(old, tree_type, &t1.size, NULL);
        if (!tree1)
                die("unable to read source tree (%s)", sha1_to_hex(old));
-       tree2 = read_object_with_reference(new, "tree", &t2.size, NULL);
+       tree2 = read_object_with_reference(new, tree_type, &t2.size, NULL);
        if (!tree2)
                die("unable to read destination tree (%s)", sha1_to_hex(new));
        t1.buf = tree1;
@@ -248,6 +243,24 @@ int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const cha
        return retval;
 }
 
+int diff_root_tree_sha1(const unsigned char *new, const char *base, struct diff_options *opt)
+{
+       int retval;
+       void *tree;
+       struct tree_desc empty, real;
+
+       tree = read_object_with_reference(new, tree_type, &real.size, NULL);
+       if (!tree)
+               die("unable to read root tree (%s)", sha1_to_hex(new));
+       real.buf = tree;
+
+       empty.size = 0;
+       empty.buf = "";
+       retval = diff_tree(&empty, &real, base, opt);
+       free(tree);
+       return retval;
+}
+
 static int count_paths(const char **paths)
 {
        int i = 0;
@@ -256,19 +269,28 @@ static int count_paths(const char **paths)
        return i;
 }
 
-void diff_tree_setup_paths(const char **p)
+void diff_tree_release_paths(struct diff_options *opt)
 {
+       free(opt->pathlens);
+}
+
+void diff_tree_setup_paths(const char **p, struct diff_options *opt)
+{
+       opt->nr_paths = 0;
+       opt->pathlens = NULL;
+       opt->paths = NULL;
+
        if (p) {
                int i;
 
-               paths = p;
-               nr_paths = count_paths(paths);
-               if (nr_paths == 0) {
-                       pathlens = NULL;
+               opt->paths = p;
+               opt->nr_paths = count_paths(p);
+               if (opt->nr_paths == 0) {
+                       opt->pathlens = NULL;
                        return;
                }
-               pathlens = xmalloc(nr_paths * sizeof(int));
-               for (i=0; i<nr_paths; i++)
-                       pathlens[i] = strlen(paths[i]);
+               opt->pathlens = xmalloc(opt->nr_paths * sizeof(int));
+               for (i=0; i < opt->nr_paths; i++)
+                       opt->pathlens[i] = strlen(p[i]);
        }
 }