git-clone: exit early if repo isn't specified
[gitweb.git] / diff-tree.c
index 65bb9d66c5610b2ede11f03a9120da48c59629f8..f55a35a9d5f9ae4e3f7d3fd778a953cc9cc533ad 100644 (file)
 #include "cache.h"
+#include "diff.h"
+#include "commit.h"
 
-static int recursive = 0;
-static int line_termination = '\n';
+static int show_root_diff = 0;
+static int no_commit_id = 0;
+static int verbose_header = 0;
+static int ignore_merges = 1;
+static int combine_merges = 0;
+static int dense_combined_merges = 0;
+static int read_stdin = 0;
+static int always_show_header = 0;
 
-static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
+static const char *header = NULL;
+static const char *header_prefix = "";
+static enum cmit_fmt commit_format = CMIT_FMT_RAW;
 
-static void update_tree_entry(void **bufp, unsigned long *sizep)
+static struct diff_options diff_options;
+
+static int call_diff_flush(void)
 {
-       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;
+       diffcore_std(&diff_options);
+       if (diff_queue_is_empty()) {
+               int saved_fmt = diff_options.output_format;
+               diff_options.output_format = DIFF_FORMAT_NO_OUTPUT;
+               diff_flush(&diff_options);
+               diff_options.output_format = saved_fmt;
+               return 0;
+       }
+       if (header) {
+               if (!no_commit_id)
+                       printf("%s%c", header, diff_options.line_termination);
+               header = NULL;
+       }
+       diff_flush(&diff_options);
+       return 1;
 }
 
-static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
+static int diff_tree_sha1_top(const unsigned char *old,
+                             const unsigned char *new, const char *base)
 {
-       int len = strlen(tree)+1;
-       const unsigned char *sha1 = tree + len;
-       const char *path = strchr(tree, ' ');
-
-       if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
-               die("corrupt tree file");
-       *pathp = path+1;
-       return sha1;
+       int ret;
+
+       ret = diff_tree_sha1(old, new, base, &diff_options);
+       call_diff_flush();
+       return ret;
 }
 
-static char *malloc_base(const char *base, const char *path, int pathlen)
+static int diff_root_tree(const unsigned char *new, const char *base)
 {
-       int baselen = strlen(base);
-       char *newbase = malloc(baselen + pathlen + 2);
-       memcpy(newbase, base, baselen);
-       memcpy(newbase + baselen, path, pathlen);
-       memcpy(newbase + baselen + pathlen, "/", 2);
-       return newbase;
-}
+       int retval;
+       void *tree;
+       struct tree_desc empty, real;
 
-static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
+       tree = read_object_with_reference(new, "tree", &real.size, NULL);
+       if (!tree)
+               die("unable to read root tree (%s)", sha1_to_hex(new));
+       real.buf = tree;
 
-/* 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) {
-               show_file(prefix, tree, size, base);
-               update_tree_entry(&tree, &size);
-       }
+       empty.buf = "";
+       empty.size = 0;
+       retval = diff_tree(&empty, &real, base, &diff_options);
+       free(tree);
+       call_diff_flush();
+       return retval;
 }
 
-/* A file entry went away or appeared */
-static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
+static const char *generate_header(const unsigned char *commit_sha1,
+                                  const unsigned char *parent_sha1,
+                                  const struct commit *commit)
 {
-       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;
-       }
+       static char this_header[16384];
+       int offset;
+       unsigned long len;
+       int abbrev = diff_options.abbrev;
+       const char *msg = commit->buffer;
+
+       if (!verbose_header)
+               return sha1_to_hex(commit_sha1);
+
+       len = strlen(msg);
 
-       printf("%s%o\t%s\t%s\t%s%s%c", prefix, mode,
-              S_ISDIR(mode) ? "tree" : "blob",
-              sha1_to_hex(sha1), base, path,
-              line_termination);
+       offset = sprintf(this_header, "%s%s ",
+                        header_prefix,
+                        diff_unique_abbrev(commit_sha1, abbrev));
+       if (commit_sha1 != parent_sha1)
+               offset += sprintf(this_header + offset, "(from %s)\n",
+                                 parent_sha1
+                                 ? diff_unique_abbrev(parent_sha1, abbrev)
+                                 : "root");
+       else
+               offset += sprintf(this_header + offset, "(from parents)\n");
+       offset += pretty_print_commit(commit_format, commit, len,
+                                     this_header + offset,
+                                     sizeof(this_header) - offset, abbrev);
+       if (always_show_header) {
+               puts(this_header);
+               return NULL;
+       }
+       return this_header;
 }
 
-static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
+static int diff_tree_commit(struct commit *commit)
 {
-       unsigned mode1, mode2;
-       const char *path1, *path2;
-       const unsigned char *sha1, *sha2;
-       int cmp, pathlen1, pathlen2;
-       char old_sha1_hex[50];
-
-       sha1 = extract(tree1, size1, &path1, &mode1);
-       sha2 = extract(tree2, size2, &path2, &mode2);
-
-       pathlen1 = strlen(path1);
-       pathlen2 = strlen(path2);
-       cmp = cache_name_compare(path1, pathlen1, path2, pathlen2);
-       if (cmp < 0) {
-               show_file("-", tree1, size1, base);
-               return -1;
-       }
-       if (cmp > 0) {
-               show_file("+", tree2, size2, base);
-               return 1;
-       }
-       if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
-               return 0;
+       struct commit_list *parents;
+       unsigned const char *sha1 = commit->object.sha1;
 
-       /*
-        * 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;
+       /* Root commit? */
+       if (show_root_diff && !commit->parents) {
+               header = generate_header(sha1, NULL, commit);
+               diff_root_tree(sha1, "");
        }
 
-       if (recursive && S_ISDIR(mode1)) {
-               int retval;
-               char *newbase = malloc_base(base, path1, pathlen1);
-               retval = diff_tree_sha1(sha1, sha2, newbase);
-               free(newbase);
-               return retval;
+       /* More than one parent? */
+       if (commit->parents && commit->parents->next) {
+               if (ignore_merges)
+                       return 0;
+               else if (combine_merges) {
+                       header = generate_header(sha1, sha1, commit);
+                       header = diff_tree_combined_merge(sha1, header,
+                                                       dense_combined_merges,
+                                                       &diff_options);
+                       if (!header && verbose_header)
+                               header_prefix = "\ndiff-tree ";
+                       return 0;
+               }
        }
 
-       strcpy(old_sha1_hex, sha1_to_hex(sha1));
-       printf("*%o->%o\t%s\t%s->%s\t%s%s%c", mode1, mode2,
-              S_ISDIR(mode1) ? "tree" : "blob",
-              old_sha1_hex, sha1_to_hex(sha2), base, path1,
-              line_termination);
-       return 0;
-}
-
-static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
-{
-       while (size1 | size2) {
-               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;
+       for (parents = commit->parents; parents; parents = parents->next) {
+               struct commit *parent = parents->item;
+               header = generate_header(sha1, parent->object.sha1, commit);
+               diff_tree_sha1_top(parent->object.sha1, sha1, "");
+               if (!header && verbose_header) {
+                       header_prefix = "\ndiff-tree ";
+                       /*
+                        * Don't print multiple merge entries if we
+                        * don't print the diffs.
+                        */
                }
-               die("diff-tree: internal error");
        }
        return 0;
 }
 
-static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
+static int diff_tree_commit_sha1(const unsigned char *sha1)
 {
-       void *tree1, *tree2;
-       unsigned long size1, size2;
-       char type[20];
-       int retval;
-
-       tree1 = read_sha1_file(old, type, &size1);
-       if (!tree1 || strcmp(type, "tree"))
-               die("unable to read source tree (%s)", sha1_to_hex(old));
-       tree2 = read_sha1_file(new, type, &size2);
-       if (!tree2 || strcmp(type, "tree"))
-               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;
+       struct commit *commit = lookup_commit_reference(sha1);
+       if (!commit)
+               return -1;
+       return diff_tree_commit(commit);
 }
 
-static void commit_to_tree(unsigned char *sha1)
+static int diff_tree_stdin(char *line)
 {
-       void *buf;
-       char type[20];
-       unsigned long size;
-
-       buf = read_sha1_file(sha1, type, &size);
-       if (buf) {
-               if (!strcmp(type, "commit"))
-                       get_sha1_hex(buf+5, sha1);
-               free(buf);
+       int len = strlen(line);
+       unsigned char sha1[20];
+       struct commit *commit;
+
+       if (!len || line[len-1] != '\n')
+               return -1;
+       line[len-1] = 0;
+       if (get_sha1_hex(line, sha1))
+               return -1;
+       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;
+               }
        }
+       return diff_tree_commit(commit);
 }
 
-int main(int argc, char **argv)
+static const char diff_tree_usage[] =
+"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)
 {
-       unsigned char old[20], new[20];
+       int nr_sha1;
+       char line[1000];
+       unsigned char sha1[2][20];
+       const char *prefix = setup_git_directory();
+
+       git_config(git_diff_config);
+       nr_sha1 = 0;
+       diff_setup(&diff_options);
+
+       for (;;) {
+               int diff_opt_cnt;
+               const char *arg;
 
-       while (argc > 3) {
-               char *arg = argv[1];
                argv++;
                argc--;
+               arg = *argv;
+               if (!arg)
+                       break;
+
+               if (*arg != '-') {
+                       if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
+                               nr_sha1++;
+                               continue;
+                       }
+                       break;
+               }
+
+               diff_opt_cnt = diff_opt_parse(&diff_options, argv, argc);
+               if (diff_opt_cnt < 0)
+                       usage(diff_tree_usage);
+               else if (diff_opt_cnt) {
+                       argv += diff_opt_cnt - 1;
+                       argc -= diff_opt_cnt - 1;
+                       continue;
+               }
+
+
+               if (!strcmp(arg, "--")) {
+                       argv++;
+                       argc--;
+                       break;
+               }
                if (!strcmp(arg, "-r")) {
-                       recursive = 1;
+                       diff_options.recursive = 1;
+                       continue;
+               }
+               if (!strcmp(arg, "-t")) {
+                       diff_options.recursive = 1;
+                       diff_options.tree_in_recursive = 1;
+                       continue;
+               }
+               if (!strcmp(arg, "-m")) {
+                       ignore_merges = 0;
+                       continue;
+               }
+               if (!strcmp(arg, "-c")) {
+                       combine_merges = 1;
+                       continue;
+               }
+               if (!strcmp(arg, "--cc")) {
+                       dense_combined_merges = combine_merges = 1;
                        continue;
                }
-               if (!strcmp(arg, "-z")) {
-                       line_termination = '\0';
+               if (!strcmp(arg, "-v")) {
+                       verbose_header = 1;
+                       header_prefix = "diff-tree ";
                        continue;
                }
-               usage("diff-tree [-r] [-z] <tree sha1> <tree sha1>");
+               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;
+               }
+               if (!strcmp(arg, "--no-commit-id")) {
+                       no_commit_id = 1;
+                       continue;
+               }
+               if (!strcmp(arg, "--always")) {
+                       always_show_header = 1;
+                       continue;
+               }
+               usage(diff_tree_usage);
        }
 
-       if (argc != 3 || get_sha1_hex(argv[1], old) || get_sha1_hex(argv[2], new))
-               usage("diff-tree <tree sha1> <tree sha1>");
-       commit_to_tree(old);
-       commit_to_tree(new);
-       return diff_tree_sha1(old, new, "");
+       if (combine_merges)
+               ignore_merges = 0;
+
+       /* We can only do dense combined merges with diff output */
+       if (dense_combined_merges)
+               diff_options.output_format = DIFF_FORMAT_PATCH;
+
+       if (diff_options.output_format == DIFF_FORMAT_PATCH)
+               diff_options.recursive = 1;
+
+       diff_tree_setup_paths(get_pathspec(prefix, argv));
+       diff_setup_done(&diff_options);
+
+       switch (nr_sha1) {
+       case 0:
+               if (!read_stdin)
+                       usage(diff_tree_usage);
+               break;
+       case 1:
+               diff_tree_commit_sha1(sha1[0]);
+               break;
+       case 2:
+               diff_tree_sha1_top(sha1[0], sha1[1], "");
+               break;
+       }
+
+       if (!read_stdin)
+               return 0;
+
+       if (diff_options.detect_rename)
+               diff_options.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
+                                      DIFF_SETUP_USE_CACHE);
+       while (fgets(line, sizeof(line), stdin))
+               diff_tree_stdin(line);
+
+       return 0;
 }