Use a *real* built-in diff generator
[gitweb.git] / cat-file.c
index 6ff9d5576a4317020b5a42cb90846668a2a6ca40..1a613f3ee5ab4197fe18355ae65f2c9226b348cf 100644 (file)
@@ -4,6 +4,92 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
+#include "exec_cmd.h"
+
+static void flush_buffer(const char *buf, unsigned long size)
+{
+       while (size > 0) {
+               long ret = xwrite(1, buf, size);
+               if (ret < 0) {
+                       /* Ignore epipe */
+                       if (errno == EPIPE)
+                               break;
+                       die("git-cat-file: %s", strerror(errno));
+               } else if (!ret) {
+                       die("git-cat-file: disk full?");
+               }
+               size -= ret;
+               buf += ret;
+       }
+}
+
+static int pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
+{
+       /* the parser in tag.c is useless here. */
+       const char *endp = buf + size;
+       const char *cp = buf;
+
+       while (cp < endp) {
+               char c = *cp++;
+               if (c != '\n')
+                       continue;
+               if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
+                       const char *tagger = cp;
+
+                       /* Found the tagger line.  Copy out the contents
+                        * of the buffer so far.
+                        */
+                       flush_buffer(buf, cp - buf);
+
+                       /*
+                        * Do something intelligent, like pretty-printing
+                        * the date.
+                        */
+                       while (cp < endp) {
+                               if (*cp++ == '\n') {
+                                       /* tagger to cp is a line
+                                        * that has ident and time.
+                                        */
+                                       const char *sp = tagger;
+                                       char *ep;
+                                       unsigned long date;
+                                       long tz;
+                                       while (sp < cp && *sp != '>')
+                                               sp++;
+                                       if (sp == cp) {
+                                               /* give up */
+                                               flush_buffer(tagger,
+                                                            cp - tagger);
+                                               break;
+                                       }
+                                       while (sp < cp &&
+                                              !('0' <= *sp && *sp <= '9'))
+                                               sp++;
+                                       flush_buffer(tagger, sp - tagger);
+                                       date = strtoul(sp, &ep, 10);
+                                       tz = strtol(ep, NULL, 10);
+                                       sp = show_date(date, tz);
+                                       flush_buffer(sp, strlen(sp));
+                                       xwrite(1, "\n", 1);
+                                       break;
+                               }
+                       }
+                       break;
+               }
+               if (cp < endp && *cp == '\n')
+                       /* end of header */
+                       break;
+       }
+       /* At this point, we have copied out the header up to the end of
+        * the tagger line and cp points at one past \n.  It could be the
+        * next header line after the tagger line, or it could be another
+        * \n that marks the end of the headers.  We need to copy out the
+        * remainder as is.
+        */
+       if (cp < endp)
+               flush_buffer(cp, endp - cp);
+       return 0;
+}
 
 int main(int argc, char **argv)
 {
@@ -11,39 +97,66 @@ int main(int argc, char **argv)
        char type[20];
        void *buf;
        unsigned long size;
+       int opt;
 
+       setup_git_directory();
        if (argc != 3 || get_sha1(argv[2], sha1))
-               usage("cat-file [-t | tagname] <sha1>");
+               usage("git-cat-file [-t|-s|-e|-p|<type>] <sha1>");
 
-       if (!strcmp("-t", argv[1])) {
-               buf = read_sha1_file(sha1, type, &size);
-               if (buf) {
-                       buf = type;
-                       size = strlen(type);
-                       type[size] = '\n';
-                       size++;
+       opt = 0;
+       if ( argv[1][0] == '-' ) {
+               opt = argv[1][1];
+               if ( !opt || argv[1][2] )
+                       opt = -1; /* Not a single character option */
+       }
+
+       buf = NULL;
+       switch (opt) {
+       case 't':
+               if (!sha1_object_info(sha1, type, NULL)) {
+                       printf("%s\n", type);
+                       return 0;
                }
-       } else {
+               break;
+
+       case 's':
+               if (!sha1_object_info(sha1, type, &size)) {
+                       printf("%lu\n", size);
+                       return 0;
+               }
+               break;
+
+       case 'e':
+               return !has_sha1_file(sha1);
+
+       case 'p':
+               if (get_sha1(argv[2], sha1) ||
+                   sha1_object_info(sha1, type, NULL))
+                       die("Not a valid object name %s", argv[2]);
+
+               /* custom pretty-print here */
+               if (!strcmp(type, "tree"))
+                       return execl_git_cmd("ls-tree", argv[2], NULL);
+
+               buf = read_sha1_file(sha1, type, &size);
+               if (!buf)
+                       die("Cannot read object %s", argv[2]);
+               if (!strcmp(type, "tag"))
+                       return pprint_tag(sha1, buf, size);
+
+               /* otherwise just spit out the data */
+               break;
+       case 0:
                buf = read_object_with_reference(sha1, argv[1], &size, NULL);
+               break;
+
+       default:
+               die("git-cat-file: unknown option: %s\n", argv[1]);
        }
 
        if (!buf)
-               die("cat-file %s: bad file", argv[2]);
+               die("git-cat-file %s: bad file", argv[2]);
 
-       while (size > 0) {
-               long ret = write(1, buf, size);
-               if (ret < 0) {
-                       if (errno == EAGAIN)
-                               continue;
-                       /* Ignore epipe */
-                       if (errno == EPIPE)
-                               break;
-                       die("cat-file: %s", strerror(errno));
-               } else if (!ret) {
-                       die("cat-file: disk full?");
-               }
-               size -= ret;
-               buf += ret;
-       }
+       flush_buffer(buf, size);
        return 0;
 }