git-cvsimport-script: clean up documentation

[git.git] / rev-parse.c

diff --git a/rev-parse.c b/rev-parse.c
index 1f4f324..c134ffd 100644 (file)
--- a/rev-parse.c
+++ b/rev-parse.c
@@ -4,6 +4,20 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
+#include "commit.h"
+
+static char *def = NULL;
+static int no_revs = 0;
+static int single_rev = 0;
+static int revs_only = 0;
+static int do_rev_argument = 1;
+static int output_revs = 0;
+
+#define NORMAL 0
+#define REVERSED 1
+static int show_type = NORMAL;
+
+static int get_extended_sha1(char *name, unsigned char *sha1);
 
 /*
  * Some arguments are relevant "revision" arguments,
@@ -32,10 +46,105 @@ static int is_rev_argument(const char *arg)
        }
 }
 
+static void show_rev(int type, unsigned char *sha1)
+{
+       if (no_revs)
+               return;
+       output_revs++;
+       printf("%s%s\n", type == show_type ? "" : "^", sha1_to_hex(sha1));
+}
+
+static void show_rev_arg(char *rev)
+{
+       if (no_revs)
+               return;
+       puts(rev);
+}
+
+static void show_norev(char *norev)
+{
+       if (revs_only)
+               return;
+       puts(norev);
+}
+
+static void show_arg(char *arg)
+{
+       if (do_rev_argument && is_rev_argument(arg))
+               show_rev_arg(arg);
+       else
+               show_norev(arg);
+}
+
+static int get_parent(char *name, unsigned char *result, int idx)
+{
+       unsigned char sha1[20];
+       int ret = get_extended_sha1(name, sha1);
+       struct commit *commit;
+       struct commit_list *p;
+
+       if (ret)
+               return ret;
+       commit = lookup_commit_reference(sha1);
+       if (!commit)
+               return -1;
+       if (parse_commit(commit))
+               return -1;
+       p = commit->parents;
+       while (p) {
+               if (!--idx) {
+                       memcpy(result, p->item->object.sha1, 20);
+                       return 0;
+               }
+               p = p->next;
+       }
+       return -1;
+}
+
+/*
+ * This is like "get_sha1()", except it allows "sha1 expressions",
+ * notably "xyz^" for "parent of xyz"
+ */
+static int get_extended_sha1(char *name, unsigned char *sha1)
+{
+       int parent;
+       int len = strlen(name);
+
+       parent = 1;
+       if (len > 2 && name[len-1] >= '1' && name[len-1] <= '9') {
+               parent = name[len-1] - '0';
+               len--;
+       }
+       if (len > 1 && name[len-1] == '^') {
+               int ret;
+               name[len-1] = 0;
+               ret = get_parent(name, sha1, parent);
+               name[len-1] = '^';
+               if (!ret)
+                       return 0;
+       }
+       return get_sha1(name, sha1);
+}
+
+static void show_default(void)
+{
+       char *s = def;
+
+       if (s) {
+               unsigned char sha1[20];
+
+               def = NULL;
+               if (!get_extended_sha1(s, sha1)) {
+                       show_rev(NORMAL, sha1);
+                       return;
+               }
+               show_arg(s);
+       }
+}
+
 int main(int argc, char **argv)
 {
-       int i, as_is = 0, revs_only = 0, no_revs = 0;
-       char *def = NULL;
+       int i, as_is = 0;
        unsigned char sha1[20];
 
        for (i = 1; i < argc; i++) {
@@ -43,22 +152,17 @@ int main(int argc, char **argv)
                char *dotdot;
        
                if (as_is) {
-                       printf("%s\n", arg);
+                       show_norev(arg);
                        continue;
                }
                if (*arg == '-') {
                        if (!strcmp(arg, "--")) {
-                               if (def) {
-                                       printf("%s\n", def);
-                                       def = NULL;
-                               }
+                               show_default();
                                if (revs_only)
                                        break;
                                as_is = 1;
                        }
                        if (!strcmp(arg, "--default")) {
-                               if (def)
-                                       printf("%s\n", def);
                                def = argv[i+1];
                                i++;
                                continue;
@@ -71,11 +175,17 @@ int main(int argc, char **argv)
                                no_revs = 1;
                                continue;
                        }
-                       if (revs_only | no_revs) {
-                               if (is_rev_argument(arg) != revs_only)
-                                       continue;
+                       if (!strcmp(arg, "--verify")) {
+                               revs_only = 1;
+                               do_rev_argument = 0;
+                               single_rev = 1;
+                               continue;
+                       }
+                       if (!strcmp(arg, "--not")) {
+                               show_type ^= REVERSED;
+                               continue;
                        }
-                       printf("%s\n", arg);
+                       show_arg(arg);
                        continue;
                }
                dotdot = strstr(arg, "..");
@@ -83,40 +193,41 @@ int main(int argc, char **argv)
                        unsigned char end[20];
                        char *n = dotdot+2;
                        *dotdot = 0;
-                       if (!get_sha1(arg, sha1)) {
+                       if (!get_extended_sha1(arg, sha1)) {
                                if (!*n)
                                        n = "HEAD";
-                               if (!get_sha1(n, end)) {
+                               if (!get_extended_sha1(n, end)) {
                                        if (no_revs)
                                                continue;
                                        def = NULL;
-                                       printf("%s\n", sha1_to_hex(end));
-                                       printf("^%s\n", sha1_to_hex(sha1));
+                                       show_rev(NORMAL, end);
+                                       show_rev(REVERSED, sha1);
                                        continue;
                                }
                        }
                        *dotdot = '.';
                }
-               if (!get_sha1(arg, sha1)) {
+               if (!get_extended_sha1(arg, sha1)) {
                        if (no_revs)
                                continue;
                        def = NULL;
-                       printf("%s\n", sha1_to_hex(sha1));
+                       show_rev(NORMAL, sha1);
                        continue;
                }
-               if (*arg == '^' && !get_sha1(arg+1, sha1)) {
+               if (*arg == '^' && !get_extended_sha1(arg+1, sha1)) {
                        if (no_revs)
                                continue;
                        def = NULL;
-                       printf("^%s\n", sha1_to_hex(sha1));
+                       show_rev(REVERSED, sha1);
                        continue;
                }
-               if (revs_only)
-                       continue;
-               def = NULL;
-               printf("%s\n", arg);
+               show_default();
+               show_norev(arg);
+       }
+       show_default();
+       if (single_rev && output_revs != 1) {
+               fprintf(stderr, "Needed a single revision\n");
+               exit(1);
        }
-       if (def)
-               printf("%s\n", def);
        return 0;
 }