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 #include "parse-options.h"
  12 #include "diff.h"
  13 #include "userdiff.h"
  14 #include "streaming.h"
  15
  16 #define BATCH 1
  17 #define BATCH_CHECK 2
  18
  19 static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
  20 {
  21         /* the parser in tag.c is useless here. */
  22         const char *endp = buf + size;
  23         const char *cp = buf;
  24
  25         while (cp < endp) {
  26                 char c = *cp++;
  27                 if (c != '\n')
  28                         continue;
  29                 if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
  30                         const char *tagger = cp;
  31
  32                         /* Found the tagger line.  Copy out the contents
  33                          * of the buffer so far.
  34                          */
  35                         write_or_die(1, buf, cp - buf);
  36
  37                         /*
  38                          * Do something intelligent, like pretty-printing
  39                          * the date.
  40                          */
  41                         while (cp < endp) {
  42                                 if (*cp++ == '\n') {
  43                                         /* tagger to cp is a line
  44                                          * that has ident and time.
  45                                          */
  46                                         const char *sp = tagger;
  47                                         char *ep;
  48                                         unsigned long date;
  49                                         long tz;
  50                                         while (sp < cp && *sp != '>')
  51                                                 sp++;
  52                                         if (sp == cp) {
  53                                                 /* give up */
  54                                                 write_or_die(1, tagger,
  55                                                              cp - tagger);
  56                                                 break;
  57                                         }
  58                                         while (sp < cp &&
  59                                                !('0' <= *sp && *sp <= '9'))
  60                                                 sp++;
  61                                         write_or_die(1, tagger, sp - tagger);
  62                                         date = strtoul(sp, &ep, 10);
  63                                         tz = strtol(ep, NULL, 10);
  64                                         sp = show_date(date, tz, 0);
  65                                         write_or_die(1, sp, strlen(sp));
  66                                         xwrite(1, "\n", 1);
  67                                         break;
  68                                 }
  69                         }
  70                         break;
  71                 }
  72                 if (cp < endp && *cp == '\n')
  73                         /* end of header */
  74                         break;
  75         }
  76         /* At this point, we have copied out the header up to the end of
  77          * the tagger line and cp points at one past \n.  It could be the
  78          * next header line after the tagger line, or it could be another
  79          * \n that marks the end of the headers.  We need to copy out the
  80          * remainder as is.
  81          */
  82         if (cp < endp)
  83                 write_or_die(1, cp, endp - cp);
  84 }
  85
  86 static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
  87 {
  88         unsigned char sha1[20];
  89         enum object_type type;
  90         char *buf;
  91         unsigned long size;
  92         struct object_context obj_context;
  93
  94         if (get_sha1_with_context(obj_name, sha1, &obj_context))
  95                 die("Not a valid object name %s", obj_name);
  96
  97         buf = NULL;
  98         switch (opt) {
  99         case 't':
 100                 type = sha1_object_info(sha1, NULL);
 101                 if (type > 0) {
 102                         printf("%s\n", typename(type));
 103                         return 0;
 104                 }
 105                 break;
 106
 107         case 's':
 108                 type = sha1_object_info(sha1, &size);
 109                 if (type > 0) {
 110                         printf("%lu\n", size);
 111                         return 0;
 112                 }
 113                 break;
 114
 115         case 'e':
 116                 return !has_sha1_file(sha1);
 117
 118         case 'p':
 119                 type = sha1_object_info(sha1, NULL);
 120                 if (type < 0)
 121                         die("Not a valid object name %s", obj_name);
 122
 123                 /* custom pretty-print here */
 124                 if (type == OBJ_TREE) {
 125                         const char *ls_args[3] = { NULL };
 126                         ls_args[0] =  "ls-tree";
 127                         ls_args[1] =  obj_name;
 128                         return cmd_ls_tree(2, ls_args, NULL);
 129                 }
 130
 131                 if (type == OBJ_BLOB)
 132                         return stream_blob_to_fd(1, sha1, NULL, 0);
 133                 buf = read_sha1_file(sha1, &type, &size);
 134                 if (!buf)
 135                         die("Cannot read object %s", obj_name);
 136                 if (type == OBJ_TAG) {
 137                         pprint_tag(sha1, buf, size);
 138                         return 0;
 139                 }
 140
 141                 /* otherwise just spit out the data */
 142                 break;
 143
 144         case 'c':
 145                 if (!obj_context.path[0])
 146                         die("git cat-file --textconv %s: <object> must be <sha1:path>",
 147                             obj_name);
 148
 149                 if (!textconv_object(obj_context.path, obj_context.mode, sha1, &buf, &size))
 150                         die("git cat-file --textconv: unable to run textconv on %s",
 151                             obj_name);
 152                 break;
 153
 154         case 0:
 155                 if (type_from_string(exp_type) == OBJ_BLOB) {
 156                         unsigned char blob_sha1[20];
 157                         if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
 158                                 enum object_type type;
 159                                 unsigned long size;
 160                                 char *buffer = read_sha1_file(sha1, &type, &size);
 161                                 if (memcmp(buffer, "object ", 7) ||
 162                                     get_sha1_hex(buffer + 7, blob_sha1))
 163                                         die("%s not a valid tag", sha1_to_hex(sha1));
 164                                 free(buffer);
 165                         } else
 166                                 hashcpy(blob_sha1, sha1);
 167
 168                         if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
 169                                 return stream_blob_to_fd(1, blob_sha1, NULL, 0);
 170                         /*
 171                          * we attempted to dereference a tag to a blob
 172                          * and failed; there may be new dereference
 173                          * mechanisms this code is not aware of.
 174                          * fall-back to the usual case.
 175                          */
 176                 }
 177                 buf = read_object_with_reference(sha1, exp_type, &size, NULL);
 178                 break;
 179
 180         default:
 181                 die("git cat-file: unknown option: %s", exp_type);
 182         }
 183
 184         if (!buf)
 185                 die("git cat-file %s: bad file", obj_name);
 186
 187         write_or_die(1, buf, size);
 188         return 0;
 189 }
 190
 191 static int batch_one_object(const char *obj_name, int print_contents)
 192 {
 193         unsigned char sha1[20];
 194         enum object_type type = 0;
 195         unsigned long size;
 196         void *contents = contents;
 197
 198         if (!obj_name)
 199            return 1;
 200
 201         if (get_sha1(obj_name, sha1)) {
 202                 printf("%s missing\n", obj_name);
 203                 fflush(stdout);
 204                 return 0;
 205         }
 206
 207         if (print_contents == BATCH)
 208                 contents = read_sha1_file(sha1, &type, &size);
 209         else
 210                 type = sha1_object_info(sha1, &size);
 211
 212         if (type <= 0) {
 213                 printf("%s missing\n", obj_name);
 214                 fflush(stdout);
 215                 if (print_contents == BATCH)
 216                         free(contents);
 217                 return 0;
 218         }
 219
 220         printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
 221         fflush(stdout);
 222
 223         if (print_contents == BATCH) {
 224                 write_or_die(1, contents, size);
 225                 printf("\n");
 226                 fflush(stdout);
 227                 free(contents);
 228         }
 229
 230         return 0;
 231 }
 232
 233 static int batch_objects(int print_contents)
 234 {
 235         struct strbuf buf = STRBUF_INIT;
 236
 237         while (strbuf_getline(&buf, stdin, '\n') != EOF) {
 238                 int error = batch_one_object(buf.buf, print_contents);
 239                 if (error)
 240                         return error;
 241         }
 242
 243         return 0;
 244 }
 245
 246 static const char * const cat_file_usage[] = {
 247         "git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>",
 248         "git cat-file (--batch|--batch-check) < <list_of_objects>",
 249         NULL
 250 };
 251
 252 static int git_cat_file_config(const char *var, const char *value, void *cb)
 253 {
 254         if (userdiff_config(var, value) < 0)
 255                 return -1;
 256
 257         return git_default_config(var, value, cb);
 258 }
 259
 260 int cmd_cat_file(int argc, const char **argv, const char *prefix)
 261 {
 262         int opt = 0, batch = 0;
 263         const char *exp_type = NULL, *obj_name = NULL;
 264
 265         const struct option options[] = {
 266                 OPT_GROUP("<type> can be one of: blob, tree, commit, tag"),
 267                 OPT_SET_INT('t', NULL, &opt, "show object type", 't'),
 268                 OPT_SET_INT('s', NULL, &opt, "show object size", 's'),
 269                 OPT_SET_INT('e', NULL, &opt,
 270                             "exit with zero when there's no error", 'e'),
 271                 OPT_SET_INT('p', NULL, &opt, "pretty-print object's content", 'p'),
 272                 OPT_SET_INT(0, "textconv", &opt,
 273                             "for blob objects, run textconv on object's content", 'c'),
 274                 OPT_SET_INT(0, "batch", &batch,
 275                             "show info and content of objects fed from the standard input",
 276                             BATCH),
 277                 OPT_SET_INT(0, "batch-check", &batch,
 278                             "show info about objects fed from the standard input",
 279                             BATCH_CHECK),
 280                 OPT_END()
 281         };
 282
 283         git_config(git_cat_file_config, NULL);
 284
 285         if (argc != 3 && argc != 2)
 286                 usage_with_options(cat_file_usage, options);
 287
 288         argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 289
 290         if (opt) {
 291                 if (argc == 1)
 292                         obj_name = argv[0];
 293                 else
 294                         usage_with_options(cat_file_usage, options);
 295         }
 296         if (!opt && !batch) {
 297                 if (argc == 2) {
 298                         exp_type = argv[0];
 299                         obj_name = argv[1];
 300                 } else
 301                         usage_with_options(cat_file_usage, options);
 302         }
 303         if (batch && (opt || argc)) {
 304                 usage_with_options(cat_file_usage, options);
 305         }
 306
 307         if (batch)
 308                 return batch_objects(batch);
 309
 310         return cat_one_file(opt, exp_type, obj_name);
 311 }