Document git-diff whitespace flags -b and -w
[gitweb.git] / merge-recursive.c
index 7a93dd9208afda607dfc69e1e749c087251be648..cd2cc77bf47025a9dfc88f594961521c3ec8f22c 100644 (file)
@@ -56,7 +56,7 @@ static int sha_eq(const unsigned char *a, const unsigned char *b)
 {
        if (!a && !b)
                return 2;
-       return a && b && memcmp(a, b, 20) == 0;
+       return a && b && hashcmp(a, b) == 0;
 }
 
 /*
@@ -98,7 +98,7 @@ static void output_commit_title(struct commit *commit)
        if (commit->util)
                printf("virtual %s\n", (char *)commit->util);
        else {
-               printf("%s ", sha1_to_hex(commit->object.sha1));
+               printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
                if (parse_commit(commit) != 0)
                        printf("(bad commit)\n");
                else {
@@ -125,9 +125,7 @@ static int flush_cache(void)
 {
        /* flush temporary index */
        struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
-       int fd = hold_lock_file_for_update(lock, current_index_file);
-       if (fd < 0)
-               die("could not lock %s", lock->filename);
+       int fd = hold_lock_file_for_update(lock, current_index_file, 1);
        if (write_cache(fd, active_cache, active_nr) ||
                        close(fd) || commit_lock_file(lock))
                die ("unable to write %s", current_index_file);
@@ -139,8 +137,10 @@ static int flush_cache(void)
 static void setup_index(int temp)
 {
        current_index_file = temp ? temporary_index_file: original_index_file;
-       if (cache_dirty)
-               die("fatal: cache changed flush_cache();");
+       if (cache_dirty) {
+               discard_cache();
+               cache_dirty = 0;
+       }
        unlink(temporary_index_file);
        discard_cache();
 }
@@ -158,7 +158,7 @@ static struct cache_entry *make_cache_entry(unsigned int mode,
        size = cache_entry_size(len);
        ce = xcalloc(1, size);
 
-       memcpy(ce->sha1, sha1, 20);
+       hashcpy(ce->sha1, sha1);
        memcpy(ce->name, path, len);
        ce->ce_flags = create_ce_flags(len, stage);
        ce->ce_mode = create_ce_mode(mode);
@@ -283,7 +283,7 @@ static int save_files_dirs(const unsigned char *sha1,
                unsigned int mode, int stage)
 {
        int len = strlen(path);
-       char *newpath = malloc(baselen + len + 1);
+       char *newpath = xmalloc(baselen + len + 1);
        memcpy(newpath, base, baselen);
        memcpy(newpath + baselen, path, len);
        newpath[baselen + len] = '\0';
@@ -355,7 +355,7 @@ static struct path_list *get_unmerged(void)
                }
                e = item->util;
                e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
-               memcpy(e->stages[ce_stage(ce)].sha, ce->sha1, 20);
+               hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
        }
 
        return unmerged;
@@ -427,8 +427,9 @@ static struct path_list *get_renames(struct tree *tree,
        return renames;
 }
 
-int update_stages(const char *path, struct diff_filespec *o,
-               struct diff_filespec *a, struct diff_filespec *b, int clear)
+static int update_stages(const char *path, struct diff_filespec *o,
+                        struct diff_filespec *a, struct diff_filespec *b,
+                        int clear)
 {
        int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
        if (clear)
@@ -455,7 +456,7 @@ static int remove_path(const char *name)
        if (ret)
                return ret;
        len = strlen(name);
-       dirs = malloc(len+1);
+       dirs = xmalloc(len+1);
        memcpy(dirs, name, len);
        dirs[len] = '\0';
        while ((slash = strrchr(name, '/'))) {
@@ -468,10 +469,10 @@ static int remove_path(const char *name)
        return ret;
 }
 
-int remove_file(int clean, const char *path)
+static int remove_file(int clean, const char *path, int no_wd)
 {
        int update_cache = index_only || clean;
-       int update_working_directory = !index_only;
+       int update_working_directory = !index_only && !no_wd;
 
        if (update_cache) {
                if (!cache_dirty)
@@ -480,8 +481,7 @@ int remove_file(int clean, const char *path)
                if (remove_file_from_cache(path))
                        return -1;
        }
-       if (update_working_directory)
-       {
+       if (update_working_directory) {
                unlink(path);
                if (errno != ENOENT || errno != EISDIR)
                        return -1;
@@ -513,8 +513,8 @@ static char *unique_path(const char *path, const char *branch)
 
 static int mkdir_p(const char *path, unsigned long mode)
 {
-       /* path points to cache entries, so strdup before messing with it */
-       char *buf = strdup(path);
+       /* path points to cache entries, so xstrdup before messing with it */
+       char *buf = xstrdup(path);
        int result = safe_create_leading_directories(buf);
        free(buf);
        return result;
@@ -537,11 +537,11 @@ static void flush_buffer(int fd, const char *buf, unsigned long size)
        }
 }
 
-void update_file_flags(const unsigned char *sha,
-                      unsigned mode,
-                      const char *path,
-                      int update_cache,
-                      int update_wd)
+static void update_file_flags(const unsigned char *sha,
+                             unsigned mode,
+                             const char *path,
+                             int update_cache,
+                             int update_wd)
 {
        if (index_only)
                update_wd = 0;
@@ -572,7 +572,7 @@ void update_file_flags(const unsigned char *sha,
                        flush_buffer(fd, buf, size);
                        close(fd);
                } else if (S_ISLNK(mode)) {
-                       char *lnk = malloc(size + 1);
+                       char *lnk = xmalloc(size + 1);
                        memcpy(lnk, buf, size);
                        lnk[size] = '\0';
                        mkdir_p(path, 0777);
@@ -586,10 +586,10 @@ void update_file_flags(const unsigned char *sha,
                add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
 }
 
-void update_file(int clean,
-               const unsigned char *sha,
-               unsigned mode,
-               const char *path)
+static void update_file(int clean,
+                       const unsigned char *sha,
+                       unsigned mode,
+                       const char *path)
 {
        update_file_flags(sha, mode, path, index_only || clean, !index_only);
 }
@@ -636,10 +636,10 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                result.clean = 0;
                if (S_ISREG(a->mode)) {
                        result.mode = a->mode;
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
                } else {
                        result.mode = b->mode;
-                       memcpy(result.sha, b->sha1, 20);
+                       hashcpy(result.sha, b->sha1);
                }
        } else {
                if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
@@ -648,9 +648,9 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                result.mode = a->mode == o->mode ? b->mode: a->mode;
 
                if (sha_eq(a->sha1, o->sha1))
-                       memcpy(result.sha, b->sha1, 20);
+                       hashcpy(result.sha, b->sha1);
                else if (sha_eq(b->sha1, o->sha1))
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
                else if (S_ISREG(a->mode)) {
                        int code = 1, fd;
                        struct stat st;
@@ -668,9 +668,9 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                        git_unpack_file(a->sha1, src1);
                        git_unpack_file(b->sha1, src2);
 
-                       argv[2] = la = strdup(mkpath("%s/%s", branch1, a->path));
-                       argv[6] = lb = strdup(mkpath("%s/%s", branch2, b->path));
-                       argv[4] = lo = strdup(mkpath("orig/%s", o->path));
+                       argv[2] = la = xstrdup(mkpath("%s/%s", branch1, a->path));
+                       argv[6] = lb = xstrdup(mkpath("%s/%s", branch2, b->path));
+                       argv[4] = lo = xstrdup(mkpath("orig/%s", o->path));
                        argv[7] = src1;
                        argv[8] = orig;
                        argv[9] = src2,
@@ -699,7 +699,7 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                        if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
                                die("cannot merge modes?");
 
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
 
                        if (!sha_eq(a->sha1, b->sha1))
                                result.clean = 0;
@@ -724,13 +724,13 @@ static void conflict_rename_rename(struct rename *ren1,
                dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
                output("%s is a directory in %s adding as %s instead",
                       ren1_dst, branch2, dst_name1);
-               remove_file(0, ren1_dst);
+               remove_file(0, ren1_dst, 0);
        }
        if (path_list_has_path(&current_directory_set, ren2_dst)) {
                dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
                output("%s is a directory in %s adding as %s instead",
                       ren2_dst, branch1, dst_name2);
-               remove_file(0, ren2_dst);
+               remove_file(0, ren2_dst, 0);
        }
        update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
        update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
@@ -743,7 +743,7 @@ static void conflict_rename_dir(struct rename *ren1,
 {
        char *new_path = unique_path(ren1->pair->two->path, branch1);
        output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
-       remove_file(0, ren1->pair->two->path);
+       remove_file(0, ren1->pair->two->path, 0);
        update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
        free(new_path);
 }
@@ -758,7 +758,7 @@ static void conflict_rename_rename_2(struct rename *ren1,
        output("Renaming %s to %s and %s to %s instead",
               ren1->pair->one->path, new_path1,
               ren2->pair->one->path, new_path2);
-       remove_file(0, ren1->pair->two->path);
+       remove_file(0, ren1->pair->two->path, 0);
        update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
        update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
        free(new_path2);
@@ -856,7 +856,7 @@ static int process_renames(struct path_list *a_renames,
                                conflict_rename_rename(ren1, branch1, ren2, branch2);
                        } else {
                                struct merge_file_info mfi;
-                               remove_file(1, ren1_src);
+                               remove_file(1, ren1_src, 1);
                                mfi = merge_file(ren1->pair->one,
                                                 ren1->pair->two,
                                                 ren2->pair->two,
@@ -889,13 +889,11 @@ static int process_renames(struct path_list *a_renames,
                        struct diff_filespec src_other, dst_other;
                        int try_merge, stage = a_renames == renames1 ? 3: 2;
 
-                       remove_file(1, ren1_src);
+                       remove_file(1, ren1_src, 1);
 
-                       memcpy(src_other.sha1,
-                                       ren1->src_entry->stages[stage].sha, 20);
+                       hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
                        src_other.mode = ren1->src_entry->stages[stage].mode;
-                       memcpy(dst_other.sha1,
-                                       ren1->dst_entry->stages[stage].sha, 20);
+                       hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
                        dst_other.mode = ren1->dst_entry->stages[stage].mode;
 
                        try_merge = 0;
@@ -980,7 +978,7 @@ static int process_renames(struct path_list *a_renames,
 
 static unsigned char *has_sha(const unsigned char *sha)
 {
-       return memcmp(sha, null_sha1, 20) == 0 ? NULL: (unsigned char *)sha;
+       return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
 }
 
 /* Per entry merge function */
@@ -1009,7 +1007,8 @@ static int process_entry(const char *path, struct stage_data *entry,
                         * unchanged in the other */
                        if (a_sha)
                                output("Removing %s", path);
-                       remove_file(1, path);
+                       /* do not touch working file if it did not exist */
+                       remove_file(1, path, !a_sha);
                } else {
                        /* Deleted in one and changed in the other */
                        clean_merge = 0;
@@ -1056,7 +1055,7 @@ static int process_entry(const char *path, struct stage_data *entry,
                        output("CONFLICT (%s): There is a directory with name %s in %s. "
                               "Adding %s as %s",
                               conf, path, other_branch, path, new_path);
-                       remove_file(0, path);
+                       remove_file(0, path, 0);
                        update_file(0, sha, mode, new_path);
                } else {
                        output("Adding %s", path);
@@ -1084,7 +1083,7 @@ static int process_entry(const char *path, struct stage_data *entry,
                        output("CONFLICT (add/add): File %s added non-identically "
                               "in both branches. Adding as %s and %s instead.",
                               path, new_path1, new_path2);
-                       remove_file(0, path);
+                       remove_file(0, path, 0);
                        update_file(0, a_sha, a_mode, new_path1);
                        update_file(0, b_sha, b_mode, new_path2);
                }
@@ -1096,11 +1095,11 @@ static int process_entry(const char *path, struct stage_data *entry,
 
                output("Auto-merging %s", path);
                o.path = a.path = b.path = (char *)path;
-               memcpy(o.sha1, o_sha, 20);
+               hashcpy(o.sha1, o_sha);
                o.mode = o_mode;
-               memcpy(a.sha1, a_sha, 20);
+               hashcpy(a.sha1, a_sha);
                a.mode = a_mode;
-               memcpy(b.sha1, b_sha, 20);
+               hashcpy(b.sha1, b_sha);
                b.mode = b_mode;
 
                mfi = merge_file(&o, &a, &b,
@@ -1191,18 +1190,28 @@ static int merge_trees(struct tree *head,
        return clean;
 }
 
+static struct commit_list *reverse_commit_list(struct commit_list *list)
+{
+       struct commit_list *next = NULL, *current, *backup;
+       for (current = list; current; current = backup) {
+               backup = current->next;
+               current->next = next;
+               next = current;
+       }
+       return next;
+}
+
 /*
  * Merge the commits h1 and h2, return the resulting virtual
  * commit object and a flag indicating the cleaness of the merge.
  */
-static
-int merge(struct commit *h1,
-                         struct commit *h2,
-                         const char *branch1,
-                         const char *branch2,
-                         int call_depth /* =0 */,
-                         struct commit *ancestor /* =None */,
-                         struct commit **result)
+static int merge(struct commit *h1,
+                struct commit *h2,
+                const char *branch1,
+                const char *branch2,
+                int call_depth /* =0 */,
+                struct commit *ancestor /* =None */,
+                struct commit **result)
 {
        struct commit_list *ca = NULL, *iter;
        struct commit *merged_common_ancestors;
@@ -1216,13 +1225,22 @@ int merge(struct commit *h1,
        if (ancestor)
                commit_list_insert(ancestor, &ca);
        else
-               ca = get_merge_bases(h1, h2, 1);
+               ca = reverse_commit_list(get_merge_bases(h1, h2, 1));
 
        output("found %u common ancestor(s):", commit_list_count(ca));
        for (iter = ca; iter; iter = iter->next)
                output_commit_title(iter->item);
 
        merged_common_ancestors = pop_commit(&ca);
+       if (merged_common_ancestors == NULL) {
+               /* if there is no common ancestor, make an empty tree */
+               struct tree *tree = xcalloc(1, sizeof(struct tree));
+
+               tree->object.parsed = 1;
+               tree->object.type = OBJ_TREE;
+               hash_sha1_file(NULL, 0, tree_type, tree->object.sha1);
+               merged_common_ancestors = make_virtual_commit(tree, "ancestor");
+       }
 
        for (iter = ca; iter; iter = iter->next) {
                output_indent = call_depth + 1;
@@ -1290,12 +1308,13 @@ int main(int argc, char *argv[])
        const char *branch1, *branch2;
        struct commit *result, *h1, *h2;
 
+       git_config(git_default_config); /* core.filemode */
        original_index_file = getenv("GIT_INDEX_FILE");
 
        if (!original_index_file)
-               original_index_file = strdup(git_path("index"));
+               original_index_file = xstrdup(git_path("index"));
 
-       temporary_index_file = strdup(git_path("mrg-rcrsv-tmp-idx"));
+       temporary_index_file = xstrdup(git_path("mrg-rcrsv-tmp-idx"));
 
        if (argc < 4)
                die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);