s/SHELL/SHELL_PATH/ in Makefile
[git.git] / rev-parse.c
index 4bd58eb..b82f294 100644 (file)
@@ -6,22 +6,24 @@
 #include "cache.h"
 #include "commit.h"
 #include "refs.h"
+#include "quote.h"
+
+#define DO_REVS                1
+#define DO_NOREV       2
+#define DO_FLAGS       4
+#define DO_NONFLAGS    8
+static int filter = ~0;
 
 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;
-static int flags_only = 0;
-static int no_flags = 0;
-static int output_sq = 0;
 
 #define NORMAL 0
 #define REVERSED 1
 static int show_type = NORMAL;
+static int symbolic = 0;
+static int abbrev = 0;
+static int output_sq = 0;
 
-static int get_extended_sha1(char *name, unsigned char *sha1);
+static int revs_count = 0;
 
 /*
  * Some arguments are relevant "revision" arguments,
@@ -31,25 +33,43 @@ static int get_extended_sha1(char *name, unsigned char *sha1);
 static int is_rev_argument(const char *arg)
 {
        static const char *rev_args[] = {
-               "--max-count=",
+               "--all",
+               "--bisect",
+               "--dense",
+               "--header",
                "--max-age=",
-               "--min-age=",
+               "--max-count=",
                "--merge-order",
+               "--min-age=",
+               "--no-merges",
+               "--objects",
+               "--parents",
+               "--pretty",
+               "--show-breaks",
+               "--sparse",
+               "--topo-order",
+               "--unpacked",
                NULL
        };
        const char **p = rev_args;
 
+       /* accept -<digit>, like traditional "head" */
+       if ((*arg == '-') && isdigit(arg[1]))
+               return 1;
+
        for (;;) {
                const char *str = *p++;
                int len;
                if (!str)
                        return 0;
                len = strlen(str);
-               if (!strncmp(arg, str, len))
+               if (!strcmp(arg, str) ||
+                   (str[len-1] == '=' && !strncmp(arg, str, len)))
                        return 1;
        }
 }
 
+/* Output argument as a string, either SQ or normal */
 static void show(const char *arg)
 {
        if (output_sq) {
@@ -68,262 +88,115 @@ static void show(const char *arg)
                puts(arg);
 }
 
-static void show_rev(int type, const unsigned char *sha1)
+/* Output a revision, only if filter allows it */
+static void show_rev(int type, const unsigned char *sha1, const char *name)
 {
-       if (no_revs)
+       if (!(filter & DO_REVS))
                return;
-       output_revs++;
+       def = NULL;
+       revs_count++;
 
-       /* Hexadecimal string plus possibly a carret;
-        * this does not have to be quoted even under output_sq.
-        */
-       printf("%s%s%c", type == show_type ? "" : "^", sha1_to_hex(sha1),
-              output_sq ? ' ' : '\n');
-}
-
-static void show_rev_arg(char *rev)
-{
-       if (no_revs)
-               return;
-       show(rev);
-}
-
-static void show_norev(char *norev)
-{
-       if (flags_only)
-               return;
-       if (revs_only)
-               return;
-       show(norev);
-}
-
-static void show_arg(char *arg)
-{
-       if (no_flags)
-               return;
-       if (do_rev_argument && is_rev_argument(arg))
-               show_rev_arg(arg);
+       if (type != show_type)
+               putchar('^');
+       if (symbolic && name)
+               show(name);
+       else if (abbrev)
+               show(find_unique_abbrev(sha1, abbrev));
        else
-               show_norev(arg);
+               show(sha1_to_hex(sha1));
 }
 
-static int get_parent(char *name, unsigned char *result, int idx)
+/* Output a flag, only if filter allows it. */
+static int show_flag(char *arg)
 {
-       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;
-       if (!idx) {
-               memcpy(result, commit->object.sha1, 20);
+       if (!(filter & DO_FLAGS))
                return 0;
+       if (filter & (is_rev_argument(arg) ? DO_REVS : DO_NOREV)) {
+               show(arg);
+               return 1;
        }
-       p = commit->parents;
-       while (p) {
-               if (!--idx) {
-                       memcpy(result, p->item->object.sha1, 20);
-                       return 0;
-               }
-               p = p->next;
-       }
-       return -1;
-}
-
-static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
-{
-       static char dirname[PATH_MAX];
-       char hex[40];
-       DIR *dir;
-       int found;
-
-       snprintf(dirname, sizeof(dirname), "%s/%.2s", get_object_directory(), name);
-       dir = opendir(dirname);
-       sprintf(hex, "%.2s", name);
-       found = 0;
-       if (dir) {
-               struct dirent *de;
-               while ((de = readdir(dir)) != NULL) {
-                       if (strlen(de->d_name) != 38)
-                               continue;
-                       if (memcmp(de->d_name, name + 2, len-2))
-                               continue;
-                       memcpy(hex + 2, de->d_name, 38);
-                       if (++found > 1)
-                               break;
-               }
-               closedir(dir);
-       }
-       if (found == 1)
-               return get_sha1_hex(hex, sha1) == 0;
        return 0;
 }
 
-static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
-{
-       do {
-               if (*a != *b)
-                       return 0;
-               a++;
-               b++;
-               len -= 2;
-       } while (len > 1);
-       if (len)
-               if ((*a ^ *b) & 0xf0)
-                       return 0;
-       return 1;
-}
-
-static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
+static void show_default(void)
 {
-       struct packed_git *p;
+       char *s = def;
 
-       prepare_packed_git();
-       for (p = packed_git; p; p = p->next) {
-               unsigned num = num_packed_objects(p);
-               unsigned first = 0, last = num;
-               while (first < last) {
-                       unsigned mid = (first + last) / 2;
-                       unsigned char now[20];
-                       int cmp;
+       if (s) {
+               unsigned char sha1[20];
 
-                       nth_packed_object_sha1(p, mid, now);
-                       cmp = memcmp(match, now, 20);
-                       if (!cmp) {
-                               first = mid;
-                               break;
-                       }
-                       if (cmp > 0) {
-                               first = mid+1;
-                               continue;
-                       }
-                       last = mid;
+               def = NULL;
+               if (!get_sha1(s, sha1)) {
+                       show_rev(NORMAL, sha1, s);
+                       return;
                }
-               if (first < num) {
-                       unsigned char now[20], next[20];
-                       nth_packed_object_sha1(p, first, now);
-                       if (match_sha(len, match, now)) {
-                               if (nth_packed_object_sha1(p, first+1, next) || !match_sha(len, match, next)) {
-                                       memcpy(sha1, now, 20);
-                                       return 1;
-                               }
-                       }
-               }       
        }
-       return 0;
 }
 
-static int get_short_sha1(char *name, unsigned char *sha1)
+static int show_reference(const char *refname, const unsigned char *sha1)
 {
-       int i;
-       char canonical[40];
-       unsigned char res[20];
-
-       memset(res, 0, 20);
-       memset(canonical, 'x', 40);
-       for (i = 0;;i++) {
-               unsigned char c = name[i];
-               unsigned char val;
-               if (!c || i > 40)
-                       break;
-               if (c >= '0' && c <= '9')
-                       val = c - '0';
-               else if (c >= 'a' && c <= 'f')
-                       val = c - 'a' + 10;
-               else if (c >= 'A' && c <='F') {
-                       val = c - 'A' + 10;
-                       c -= 'A' - 'a';
-               }
-               else
-                       return -1;
-               canonical[i] = c;
-               if (!(i & 1))
-                       val <<= 4;
-               res[i >> 1] |= val;
-       }
-       if (i < 4)
-               return -1;
-       if (find_short_object_filename(i, canonical, sha1))
-               return 0;
-       if (find_short_packed_object(i, res, sha1))
-               return 0;
-       return -1;
+       show_rev(NORMAL, sha1, refname);
+       return 0;
 }
 
-/*
- * 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)
+static void show_datestring(const char *flag, const char *datestr)
 {
-       int parent, ret;
-       int len = strlen(name);
+       static char buffer[100];
 
-       parent = 1;
-       if (len > 2 && name[len-1] >= '0' && name[len-1] <= '9') {
-               parent = name[len-1] - '0';
-               len--;
-       }
-       if (len > 1 && name[len-1] == '^') {
-               name[len-1] = 0;
-               ret = get_parent(name, sha1, parent);
-               name[len-1] = '^';
-               if (!ret)
-                       return 0;
-       }
-       ret = get_sha1(name, sha1);
-       if (!ret)
-               return 0;
-       return get_short_sha1(name, sha1);
+       /* date handling requires both flags and revs */
+       if ((filter & (DO_FLAGS | DO_REVS)) != (DO_FLAGS | DO_REVS))
+               return;
+       snprintf(buffer, sizeof(buffer), "%s%lu", flag, approxidate(datestr));
+       show(buffer);
 }
 
-static void show_default(void)
+static int show_file(const char *arg)
 {
-       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);
+       show_default();
+       if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
+               show(arg);
+               return 1;
        }
-}
-
-static int show_reference(const char *refname, const unsigned char *sha1)
-{
-       show_rev(NORMAL, sha1);
        return 0;
 }
 
 int main(int argc, char **argv)
 {
-       int i, as_is = 0;
+       int i, as_is = 0, verify = 0;
        unsigned char sha1[20];
-
+       const char *prefix = setup_git_directory();
+       
        for (i = 1; i < argc; i++) {
+               struct stat st;
                char *arg = argv[i];
                char *dotdot;
        
                if (as_is) {
-                       show_norev(arg);
+                       show_file(arg);
+                       continue;
+               }
+               if (!strcmp(arg,"-n")) {
+                       if (++i >= argc)
+                               die("-n requires an argument");
+                       if ((filter & DO_FLAGS) && (filter & DO_REVS)) {
+                               show(arg);
+                               show(argv[i]);
+                       }
                        continue;
                }
+               if (!strncmp(arg,"-n",2)) {
+                       if ((filter & DO_FLAGS) && (filter & DO_REVS))
+                               show(arg);
+                       continue;
+               }
+
                if (*arg == '-') {
                        if (!strcmp(arg, "--")) {
-                               show_default();
-                               if (revs_only)
-                                       break;
                                as_is = 1;
+                               /* Pass on the "--" if we show anything but files.. */
+                               if (filter & (DO_FLAGS | DO_REVS))
+                                       show_file(arg);
+                               continue;
                        }
                        if (!strcmp(arg, "--default")) {
                                def = argv[i+1];
@@ -331,25 +204,37 @@ int main(int argc, char **argv)
                                continue;
                        }
                        if (!strcmp(arg, "--revs-only")) {
-                               revs_only = 1;
+                               filter &= ~DO_NOREV;
                                continue;
                        }
                        if (!strcmp(arg, "--no-revs")) {
-                               no_revs = 1;
+                               filter &= ~DO_REVS;
                                continue;
                        }
                        if (!strcmp(arg, "--flags")) {
-                               flags_only = 1;
+                               filter &= ~DO_NONFLAGS;
                                continue;
                        }
                        if (!strcmp(arg, "--no-flags")) {
-                               no_flags = 1;
+                               filter &= ~DO_FLAGS;
                                continue;
                        }
                        if (!strcmp(arg, "--verify")) {
-                               revs_only = 1;
-                               do_rev_argument = 0;
-                               single_rev = 1;
+                               filter &= ~(DO_FLAGS|DO_NOREV);
+                               verify = 1;
+                               continue;
+                       }
+                       if (!strcmp(arg, "--short") ||
+                           !strncmp(arg, "--short=", 9)) {
+                               filter &= ~(DO_FLAGS|DO_NOREV);
+                               verify = 1;
+                               abbrev = DEFAULT_ABBREV;
+                               if (arg[8] == '=')
+                                       abbrev = strtoul(arg + 9, NULL, 10);
+                               if (abbrev < MINIMUM_ABBREV)
+                                       abbrev = MINIMUM_ABBREV;
+                               else if (40 <= abbrev)
+                                       abbrev = 40;
                                continue;
                        }
                        if (!strcmp(arg, "--sq")) {
@@ -360,53 +245,103 @@ int main(int argc, char **argv)
                                show_type ^= REVERSED;
                                continue;
                        }
+                       if (!strcmp(arg, "--symbolic")) {
+                               symbolic = 1;
+                               continue;
+                       }
                        if (!strcmp(arg, "--all")) {
                                for_each_ref(show_reference);
                                continue;
                        }
-                       show_arg(arg);
+                       if (!strcmp(arg, "--show-prefix")) {
+                               if (prefix)
+                                       puts(prefix);
+                               continue;
+                       }
+                       if (!strcmp(arg, "--show-cdup")) {
+                               const char *pfx = prefix;
+                               while (pfx) {
+                                       pfx = strchr(pfx, '/');
+                                       if (pfx) {
+                                               pfx++;
+                                               printf("../");
+                                       }
+                               }
+                               putchar('\n');
+                               continue;
+                       }
+                       if (!strcmp(arg, "--git-dir")) {
+                               const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
+                               static char cwd[PATH_MAX];
+                               if (gitdir) {
+                                       puts(gitdir);
+                                       continue;
+                               }
+                               if (!prefix) {
+                                       puts(".git");
+                                       continue;
+                               }
+                               if (!getcwd(cwd, PATH_MAX))
+                                       die("unable to get current working directory");
+                               printf("%s/.git\n", cwd);
+                               continue;
+                       }
+                       if (!strncmp(arg, "--since=", 8)) {
+                               show_datestring("--max-age=", arg+8);
+                               continue;
+                       }
+                       if (!strncmp(arg, "--after=", 8)) {
+                               show_datestring("--max-age=", arg+8);
+                               continue;
+                       }
+                       if (!strncmp(arg, "--before=", 9)) {
+                               show_datestring("--min-age=", arg+9);
+                               continue;
+                       }
+                       if (!strncmp(arg, "--until=", 8)) {
+                               show_datestring("--min-age=", arg+8);
+                               continue;
+                       }
+                       if (show_flag(arg) && verify)
+                               die("Needed a single revision");
                        continue;
                }
+
+               /* Not a flag argument */
                dotdot = strstr(arg, "..");
                if (dotdot) {
                        unsigned char end[20];
                        char *n = dotdot+2;
                        *dotdot = 0;
-                       if (!get_extended_sha1(arg, sha1)) {
+                       if (!get_sha1(arg, sha1)) {
                                if (!*n)
                                        n = "HEAD";
-                               if (!get_extended_sha1(n, end)) {
-                                       if (no_revs)
-                                               continue;
-                                       def = NULL;
-                                       show_rev(NORMAL, end);
-                                       show_rev(REVERSED, sha1);
+                               if (!get_sha1(n, end)) {
+                                       show_rev(NORMAL, end, n);
+                                       show_rev(REVERSED, sha1, arg);
                                        continue;
                                }
                        }
                        *dotdot = '.';
                }
-               if (!get_extended_sha1(arg, sha1)) {
-                       if (no_revs)
-                               continue;
-                       def = NULL;
-                       show_rev(NORMAL, sha1);
+               if (!get_sha1(arg, sha1)) {
+                       show_rev(NORMAL, sha1, arg);
                        continue;
                }
-               if (*arg == '^' && !get_extended_sha1(arg+1, sha1)) {
-                       if (no_revs)
-                               continue;
-                       def = NULL;
-                       show_rev(REVERSED, sha1);
+               if (*arg == '^' && !get_sha1(arg+1, sha1)) {
+                       show_rev(REVERSED, sha1, arg+1);
                        continue;
                }
-               show_default();
-               show_norev(arg);
+               as_is = 1;
+               if (!show_file(arg))
+                       continue;
+               if (verify)
+                       die("Needed a single revision");
+               if (lstat(arg, &st) < 0)
+                       die("'%s': %s", arg, strerror(errno));
        }
        show_default();
-       if (single_rev && output_revs != 1) {
-               fprintf(stderr, "Needed a single revision\n");
-               exit(1);
-       }
+       if (verify && revs_count != 1)
+               die("Needed a single revision");
        return 0;
 }