git log: don't do merge diffs by default
[gitweb.git] / diff-tree.c
index 0dd3cdacb2640dac7dfac3829e38b46bc450101f..7207867a74d0869c6a6b839c040321c843ee9c2f 100644 (file)
-#include <ctype.h>
 #include "cache.h"
 #include "diff.h"
 #include "commit.h"
+#include "log-tree.h"
 
-static int show_root_diff = 0;
-static int verbose_header = 0;
-static int ignore_merges = 1;
-static int recursive = 0;
-static int show_tree_entry_in_recursive = 0;
-static int read_stdin = 0;
-static int diff_output_format = DIFF_FORMAT_RAW;
-static int diff_line_termination = '\n';
-static int detect_rename = 0;
-static int find_copies_harder = 0;
-static int diff_setup_opt = 0;
-static int diff_score_opt = 0;
-static const char *pickaxe = NULL;
-static int pickaxe_opts = 0;
-static int diff_break_opt = -1;
-static const char *orderfile = NULL;
-static const char *diff_filter = NULL;
-static const char *header = NULL;
-static const char *header_prefix = "";
-static enum cmit_fmt commit_format = CMIT_FMT_RAW;
+static struct rev_info log_tree_opt;
 
-// What paths are we interested in?
-static int nr_paths = 0;
-static const char **paths = NULL;
-static int *pathlens = NULL;
-
-static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
-
-static void update_tree_entry(void **bufp, unsigned long *sizep)
-{
-       void *buf = *bufp;
-       unsigned long size = *sizep;
-       int len = strlen(buf) + 1 + 20;
-
-       if (size < len)
-               die("corrupt tree file");
-       *bufp = buf + len;
-       *sizep = size - len;
-}
-
-static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
-{
-       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);
-       memcpy(newbase + baselen + pathlen, "/", 2);
-       return newbase;
-}
-
-static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
-static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
-
-/* A file entry went away or appeared */
-static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
-{
-       unsigned mode;
-       const char *path;
-       const unsigned char *sha1 = extract(tree, size, &path, &mode);
-
-       if (recursive && S_ISDIR(mode)) {
-               char type[20];
-               unsigned long size;
-               char *newbase = malloc_base(base, path, strlen(path));
-               void *tree;
-
-               tree = read_sha1_file(sha1, type, &size);
-               if (!tree || strcmp(type, "tree"))
-                       die("corrupt tree sha %s", sha1_to_hex(sha1));
-
-               show_tree(prefix, tree, size, newbase);
-
-               free(tree);
-               free(newbase);
-               return;
-       }
-
-       diff_addremove(prefix[0], mode, sha1, base, path);
-}
-
-static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
+static int diff_tree_commit_sha1(const unsigned char *sha1)
 {
-       unsigned mode1, mode2;
-       const char *path1, *path2;
-       const unsigned char *sha1, *sha2;
-       int cmp, pathlen1, pathlen2;
-
-       sha1 = extract(tree1, size1, &path1, &mode1);
-       sha2 = extract(tree2, size2, &path2, &mode2);
-
-       pathlen1 = strlen(path1);
-       pathlen2 = strlen(path2);
-       cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
-       if (cmp < 0) {
-               show_file("-", tree1, size1, base);
+       struct commit *commit = lookup_commit_reference(sha1);
+       if (!commit)
                return -1;
-       }
-       if (cmp > 0) {
-               show_file("+", tree2, size2, base);
-               return 1;
-       }
-       if (!find_copies_harder && !memcmp(sha1, sha2, 20) && mode1 == mode2)
-               return 0;
-
-       /*
-        * If the filemode has changed to/from a directory from/to a regular
-        * file, we need to consider it a remove and an add.
-        */
-       if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
-               show_file("-", tree1, size1, base);
-               show_file("+", tree2, size2, base);
-               return 0;
-       }
-
-       if (recursive && S_ISDIR(mode1)) {
-               int retval;
-               char *newbase = malloc_base(base, path1, pathlen1);
-               if (show_tree_entry_in_recursive)
-                       diff_change(mode1, mode2, sha1, sha2, base, path1);
-               retval = diff_tree_sha1(sha1, sha2, newbase);
-               free(newbase);
-               return retval;
-       }
-
-       diff_change(mode1, mode2, sha1, sha2, base, path1);
-       return 0;
-}
-
-static int interesting(void *tree, unsigned long size, const char *base)
-{
-       const char *path;
-       unsigned mode;
-       int i;
-       int baselen, pathlen;
-
-       if (!nr_paths)
-               return 1;
-
-       (void)extract(tree, size, &path, &mode);
-
-       pathlen = strlen(path);
-       baselen = strlen(base);
-
-       for (i=0; i < nr_paths; i++) {
-               const char *match = paths[i];
-               int matchlen = pathlens[i];
-
-               if (baselen >= matchlen) {
-                       /* If it doesn't match, move along... */
-                       if (strncmp(base, match, matchlen))
-                               continue;
-
-                       /* The base is a subdirectory of a path which was specified. */
-                       return 1;
-               }
-
-               /* Does the base match? */
-               if (strncmp(base, match, baselen))
-                       continue;
-
-               match += baselen;
-               matchlen -= baselen;
-
-               if (pathlen > matchlen)
-                       continue;
-
-               if (matchlen > pathlen) {
-                       if (match[pathlen] != '/')
-                               continue;
-                       if (!S_ISDIR(mode))
-                               continue;
-               }
-
-               if (strncmp(path, match, pathlen))
-                       continue;
-
-               return 1;
-       }
-       return 0; /* No matches */
-}
-
-/* A whole sub-tree went away or appeared */
-static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
-{
-       while (size) {
-               if (interesting(tree, size, base))
-                       show_file(prefix, tree, size, base);
-               update_tree_entry(&tree, &size);
-       }
-}
-
-static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
-{
-       while (size1 | size2) {
-               if (nr_paths && size1 && !interesting(tree1, size1, base)) {
-                       update_tree_entry(&tree1, &size1);
-                       continue;
-               }
-               if (nr_paths && size2 && !interesting(tree2, size2, base)) {
-                       update_tree_entry(&tree2, &size2);
-                       continue;
-               }
-               if (!size1) {
-                       show_file("+", tree2, size2, base);
-                       update_tree_entry(&tree2, &size2);
-                       continue;
-               }
-               if (!size2) {
-                       show_file("-", tree1, size1, base);
-                       update_tree_entry(&tree1, &size1);
-                       continue;
-               }
-               switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
-               case -1:
-                       update_tree_entry(&tree1, &size1);
-                       continue;
-               case 0:
-                       update_tree_entry(&tree1, &size1);
-                       /* Fallthrough */
-               case 1:
-                       update_tree_entry(&tree2, &size2);
-                       continue;
-               }
-               die("git-diff-tree: internal error");
-       }
-       return 0;
-}
-
-static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
-{
-       void *tree1, *tree2;
-       unsigned long size1, size2;
-       int retval;
-
-       tree1 = read_object_with_reference(old, "tree", &size1, NULL);
-       if (!tree1)
-               die("unable to read source tree (%s)", sha1_to_hex(old));
-       tree2 = read_object_with_reference(new, "tree", &size2, NULL);
-       if (!tree2)
-               die("unable to read destination tree (%s)", sha1_to_hex(new));
-       retval = diff_tree(tree1, size1, tree2, size2, base);
-       free(tree1);
-       free(tree2);
-       return retval;
-}
-
-static void call_diff_setup(void)
-{
-       diff_setup(diff_setup_opt);
-}
-
-static int call_diff_flush(void)
-{
-       diffcore_std(NULL,
-                    detect_rename, diff_score_opt,
-                    pickaxe, pickaxe_opts,
-                    diff_break_opt,
-                    orderfile,
-                    diff_filter);
-       if (diff_queue_is_empty()) {
-               diff_flush(DIFF_FORMAT_NO_OUTPUT, diff_line_termination);
-               return 0;
-       }
-       if (header) {
-               printf("%s%c", header, diff_line_termination);
-               header = NULL;
-       }
-       diff_flush(diff_output_format, diff_line_termination);
-       return 1;
-}
-
-static int diff_tree_sha1_top(const unsigned char *old,
-                             const unsigned char *new, const char *base)
-{
-       int ret;
-
-       call_diff_setup();
-       ret = diff_tree_sha1(old, new, base);
-       call_diff_flush();
-       return ret;
-}
-
-static int diff_root_tree(const unsigned char *new, const char *base)
-{
-       int retval;
-       void *tree;
-       unsigned long size;
-
-       call_diff_setup();
-       tree = read_object_with_reference(new, "tree", &size, NULL);
-       if (!tree)
-               die("unable to read root tree (%s)", sha1_to_hex(new));
-       retval = diff_tree("", 0, tree, size, base);
-       free(tree);
-       call_diff_flush();
-       return retval;
-}
-
-static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
-{
-       static char this_header[16384];
-       int offset;
-
-       if (!verbose_header)
-               return commit;
-
-       offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
-       offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
-       return this_header;
-}
-
-static int diff_tree_commit(const unsigned char *commit, const char *name)
-{
-       unsigned long size, offset;
-       char *buf = read_object_with_reference(commit, "commit", &size, NULL);
-
-       if (!buf)
-               return -1;
-
-       if (!name) {
-               static char commit_name[60];
-               strcpy(commit_name, sha1_to_hex(commit));
-               name = commit_name;
-       }
-
-       /* Root commit? */
-       if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
-               header = generate_header(name, "root", buf, size);
-               diff_root_tree(commit, "");
-       }
-
-       /* More than one parent? */
-       if (ignore_merges) {
-               if (!memcmp(buf + 46 + 48, "parent ", 7))
-                       return 0;
-       }
-
-       offset = 46;
-       while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
-               unsigned char parent[20];
-               if (get_sha1_hex(buf + offset + 7, parent))
-                       return -1;
-               header = generate_header(name, sha1_to_hex(parent), buf, size);
-               diff_tree_sha1_top(parent, commit, "");
-               if (!header && verbose_header) {
-                       header_prefix = "\ndiff-tree ";
-                       /*
-                        * Don't print multiple merge entries if we
-                        * don't print the diffs.
-                        */
-               }
-               offset += 48;
-       }
-       return 0;
+       return log_tree_commit(&log_tree_opt, commit);
 }
 
 static int diff_tree_stdin(char *line)
 {
        int len = strlen(line);
-       unsigned char commit[20], parent[20];
-       static char this_header[1000];
+       unsigned char sha1[20];
+       struct commit *commit;
 
        if (!len || line[len-1] != '\n')
                return -1;
        line[len-1] = 0;
-       if (get_sha1_hex(line, commit))
+       if (get_sha1_hex(line, sha1))
                return -1;
-       if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
-               line[40] = 0;
-               line[81] = 0;
-               sprintf(this_header, "%s (from %s)\n", line, line+41);
-               header = this_header;
-               return diff_tree_sha1_top(parent, commit, "");
+       commit = lookup_commit(sha1);
+       if (!commit || parse_commit(commit))
+               return -1;
+       if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
+               /* Graft the fake parents locally to the commit */
+               int pos = 41;
+               struct commit_list **pptr, *parents;
+
+               /* Free the real parent list */
+               for (parents = commit->parents; parents; ) {
+                       struct commit_list *tmp = parents->next;
+                       free(parents);
+                       parents = tmp;
+               }
+               commit->parents = NULL;
+               pptr = &(commit->parents);
+               while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
+                       struct commit *parent = lookup_commit(sha1);
+                       if (parent) {
+                               pptr = &commit_list_insert(parent, pptr)->next;
+                       }
+                       pos += 41;
+               }
        }
-       line[40] = 0;
-       return diff_tree_commit(commit, line);
+       return log_tree_commit(&log_tree_opt, commit);
 }
 
 static const char diff_tree_usage[] =
-"git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
-"[<common diff options>] <tree-ish> <tree-ish>"
+"git-diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
+"[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
+"  -r            diff recursively\n"
+"  --root        include the initial commit as diff against /dev/null\n"
 COMMON_DIFF_OPTIONS_HELP;
 
 int main(int argc, const char **argv)
 {
        int nr_sha1;
        char line[1000];
-       unsigned char sha1[2][20];
+       struct object *tree1, *tree2;
+       static struct rev_info *opt = &log_tree_opt;
+       struct object_list *list;
+       int read_stdin = 0;
 
+       git_config(git_diff_config);
        nr_sha1 = 0;
-       for (;;) {
-               const char *arg;
-
-               argv++;
-               argc--;
-               arg = *argv;
-               if (!arg)
-                       break;
+       init_revisions(opt);
+       opt->abbrev = 0;
+       opt->diff = 1;
+       argc = setup_revisions(argc, argv, opt, NULL);
 
-               if (*arg != '-') {
-                       if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
-                               nr_sha1++;
-                               continue;
-                       }
-                       break;
-               }
+       while (--argc > 0) {
+               const char *arg = *++argv;
 
-               if (!strcmp(arg, "--")) {
-                       argv++;
-                       argc--;
-                       break;
-               }
-               if (!strcmp(arg, "-r")) {
-                       recursive = 1;
-                       continue;
-               }
-               if (!strcmp(arg, "-t")) {
-                       recursive = show_tree_entry_in_recursive = 1;
-                       continue;
-               }
-               if (!strcmp(arg, "-R")) {
-                       diff_setup_opt |= DIFF_SETUP_REVERSE;
-                       continue;
-               }
-               if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
-                       diff_output_format = DIFF_FORMAT_PATCH;
-                       recursive = 1;
-                       continue;
-               }
-               if (!strncmp(arg, "-S", 2)) {
-                       pickaxe = arg + 2;
-                       continue;
-               }
-               if (!strncmp(arg, "-O", 2)) {
-                       orderfile = arg + 2;
-                       continue;
-               }
-               if (!strncmp(arg, "--diff-filter=", 14)) {
-                       diff_filter = arg + 14;
-                       continue;
-               }
-               if (!strcmp(arg, "--pickaxe-all")) {
-                       pickaxe_opts = DIFF_PICKAXE_ALL;
-                       continue;
-               }
-               if (!strncmp(arg, "-M", 2)) {
-                       detect_rename = DIFF_DETECT_RENAME;
-                       if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
-                               usage(diff_tree_usage);
-                       continue;
-               }
-               if (!strncmp(arg, "-C", 2)) {
-                       detect_rename = DIFF_DETECT_COPY;
-                       if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
-                               usage(diff_tree_usage);
-                       continue;
-               }
-               if (!strncmp(arg, "-B", 2)) {
-                       if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
-                               usage(diff_tree_usage);
-                       continue;
-               }
-               if (!strcmp(arg, "--find-copies-harder")) {
-                       find_copies_harder = 1;
-                       continue;
-               }
-               if (!strcmp(arg, "--name-only")) {
-                       diff_output_format = DIFF_FORMAT_NAME;
-                       continue;
-               }
-               if (!strcmp(arg, "-z")) {
-                       diff_line_termination = 0;
-                       continue;
-               }
-               if (!strcmp(arg, "-m")) {
-                       ignore_merges = 0;
-                       continue;
-               }
-               if (!strcmp(arg, "-s")) {
-                       diff_output_format = DIFF_FORMAT_NO_OUTPUT;
-                       continue;
-               }
-               if (!strcmp(arg, "-v")) {
-                       verbose_header = 1;
-                       header_prefix = "diff-tree ";
-                       continue;
-               }
-               if (!strncmp(arg, "--pretty", 8)) {
-                       verbose_header = 1;
-                       header_prefix = "diff-tree ";
-                       commit_format = get_commit_format(arg+8);
-                       continue;
-               }
                if (!strcmp(arg, "--stdin")) {
                        read_stdin = 1;
                        continue;
                }
-               if (!strcmp(arg, "--root")) {
-                       show_root_diff = 1;
-                       continue;
-               }
                usage(diff_tree_usage);
        }
-       if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
-               usage(diff_tree_usage);
 
-       if (argc > 0) {
-               int i;
-
-               paths = argv;
-               nr_paths = argc;
-               pathlens = xmalloc(nr_paths * sizeof(int));
-               for (i=0; i<nr_paths; i++)
-                       pathlens[i] = strlen(paths[i]);
+       /*
+        * NOTE! "setup_revisions()" will have inserted the revisions
+        * it parsed in reverse order. So if you do
+        *
+        *      git-diff-tree a b
+        *
+        * the commit list will be "b" -> "a" -> NULL, so we reverse
+        * the order of the objects if the first one is not marked
+        * UNINTERESTING.
+        */
+       nr_sha1 = 0;
+       list = opt->pending_objects;
+       if (list) {
+               nr_sha1++;
+               tree1 = list->item;
+               list = list->next;
+               if (list) {
+                       nr_sha1++;
+                       tree2 = tree1;
+                       tree1 = list->item;
+                       if (list->next)
+                               usage(diff_tree_usage);
+                       /* Switch them around if the second one was uninteresting.. */
+                       if (tree2->flags & UNINTERESTING) {
+                               struct object *tmp = tree2;
+                               tree2 = tree1;
+                               tree1 = tmp;
+                       }
+               }
        }
 
        switch (nr_sha1) {
@@ -539,19 +121,22 @@ int main(int argc, const char **argv)
                        usage(diff_tree_usage);
                break;
        case 1:
-               diff_tree_commit(sha1[0], NULL);
+               diff_tree_commit_sha1(tree1->sha1);
                break;
        case 2:
-               diff_tree_sha1_top(sha1[0], sha1[1], "");
+               diff_tree_sha1(tree1->sha1,
+                              tree2->sha1,
+                              "", &opt->diffopt);
+               log_tree_diff_flush(opt);
                break;
        }
 
        if (!read_stdin)
                return 0;
 
-       if (detect_rename)
-               diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
-                                  DIFF_SETUP_USE_CACHE);
+       if (opt->diffopt.detect_rename)
+               opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
+                                      DIFF_SETUP_USE_CACHE);
        while (fgets(line, sizeof(line), stdin))
                diff_tree_stdin(line);