git/builtin-cat-file.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #include "cache.h"
   7 #include "exec_cmd.h"
   8 #include "tag.h"
   9 #include "tree.h"
  10 #include "builtin.h"
  11
  12 static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
  13 {
  14         /* the parser in tag.c is useless here. */
  15         const char *endp = buf + size;
  16         const char *cp = buf;
  17
  18         while (cp < endp) {
  19                 char c = *cp++;
  20                 if (c != '\n')
  21                         continue;
  22                 if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
  23                         const char *tagger = cp;
  24
  25                         /* Found the tagger line.  Copy out the contents
  26                          * of the buffer so far.
  27                          */
  28                         write_or_die(1, buf, cp - buf);
  29
  30                         /*
  31                          * Do something intelligent, like pretty-printing
  32                          * the date.
  33                          */
  34                         while (cp < endp) {
  35                                 if (*cp++ == '\n') {
  36                                         /* tagger to cp is a line
  37                                          * that has ident and time.
  38                                          */
  39                                         const char *sp = tagger;
  40                                         char *ep;
  41                                         unsigned long date;
  42                                         long tz;
  43                                         while (sp < cp && *sp != '>')
  44                                                 sp++;
  45                                         if (sp == cp) {
  46                                                 /* give up */
  47                                                 write_or_die(1, tagger,
  48                                                              cp - tagger);
  49                                                 break;
  50                                         }
  51                                         while (sp < cp &&
  52                                                !('0' <= *sp && *sp <= '9'))
  53                                                 sp++;
  54                                         write_or_die(1, tagger, sp - tagger);
  55                                         date = strtoul(sp, &ep, 10);
  56                                         tz = strtol(ep, NULL, 10);
  57                                         sp = show_date(date, tz, 0);
  58                                         write_or_die(1, sp, strlen(sp));
  59                                         xwrite(1, "\n", 1);
  60                                         break;
  61                                 }
  62                         }
  63                         break;
  64                 }
  65                 if (cp < endp && *cp == '\n')
  66                         /* end of header */
  67                         break;
  68         }
  69         /* At this point, we have copied out the header up to the end of
  70          * the tagger line and cp points at one past \n.  It could be the
  71          * next header line after the tagger line, or it could be another
  72          * \n that marks the end of the headers.  We need to copy out the
  73          * remainder as is.
  74          */
  75         if (cp < endp)
  76                 write_or_die(1, cp, endp - cp);
  77 }
  78
  79 int cmd_cat_file(int argc, const char **argv, const char *prefix)
  80 {
  81         unsigned char sha1[20];
  82         enum object_type type;
  83         void *buf;
  84         unsigned long size;
  85         int opt;
  86         const char *exp_type, *obj_name;
  87
  88         git_config(git_default_config);
  89         if (argc != 3)
  90                 usage("git-cat-file [-t|-s|-e|-p|<type>] <sha1>");
  91         exp_type = argv[1];
  92         obj_name = argv[2];
  93
  94         if (get_sha1(obj_name, sha1))
  95                 die("Not a valid object name %s", obj_name);
  96
  97         opt = 0;
  98         if ( exp_type[0] == '-' ) {
  99                 opt = exp_type[1];
 100                 if ( !opt || exp_type[2] )
 101                         opt = -1; /* Not a single character option */
 102         }
 103
 104         buf = NULL;
 105         switch (opt) {
 106         case 't':
 107                 type = sha1_object_info(sha1, NULL);
 108                 if (type > 0) {
 109                         printf("%s\n", typename(type));
 110                         return 0;
 111                 }
 112                 break;
 113
 114         case 's':
 115                 type = sha1_object_info(sha1, &size);
 116                 if (type > 0) {
 117                         printf("%lu\n", size);
 118                         return 0;
 119                 }
 120                 break;
 121
 122         case 'e':
 123                 return !has_sha1_file(sha1);
 124
 125         case 'p':
 126                 type = sha1_object_info(sha1, NULL);
 127                 if (type < 0)
 128                         die("Not a valid object name %s", obj_name);
 129
 130                 /* custom pretty-print here */
 131                 if (type == OBJ_TREE) {
 132                         const char *ls_args[3] = {"ls-tree", obj_name, NULL};
 133                         return cmd_ls_tree(2, ls_args, NULL);
 134                 }
 135
 136                 buf = read_sha1_file(sha1, &type, &size);
 137                 if (!buf)
 138                         die("Cannot read object %s", obj_name);
 139                 if (type == OBJ_TAG) {
 140                         pprint_tag(sha1, buf, size);
 141                         return 0;
 142                 }
 143
 144                 /* otherwise just spit out the data */
 145                 break;
 146         case 0:
 147                 buf = read_object_with_reference(sha1, exp_type, &size, NULL);
 148                 break;
 149
 150         default:
 151                 die("git-cat-file: unknown option: %s\n", exp_type);
 152         }
 153
 154         if (!buf)
 155                 die("git-cat-file %s: bad file", obj_name);
 156
 157         write_or_die(1, buf, size);
 158         return 0;
 159 }