examples/cat-file.c

   1 /*
   2  * libgit2 "cat-file" example - shows how to print data from the ODB
   3  *
   4  * Written by the libgit2 contributors
   5  *
   6  * To the extent possible under law, the author(s) have dedicated all copyright
   7  * and related and neighboring rights to this software to the public domain
   8  * worldwide. This software is distributed without any warranty.
   9  *
  10  * You should have received a copy of the CC0 Public Domain Dedication along
  11  * with this software. If not, see
  12  * <http://creativecommons.org/publicdomain/zero/1.0/>.
  13  */
  14
  15 #include "common.h"
  16
  17 static void print_signature(const char *header, const git_signature *sig)
  18 {
  19         char sign;
  20         int offset, hours, minutes;
  21
  22         if (!sig)
  23                 return;
  24
  25         offset = sig->when.offset;
  26         if (offset < 0) {
  27                 sign = '-';
  28                 offset = -offset;
  29         } else {
  30                 sign = '+';
  31         }
  32
  33         hours   = offset / 60;
  34         minutes = offset % 60;
  35
  36         printf("%s %s <%s> %ld %c%02d%02d\n",
  37                    header, sig->name, sig->email, (long)sig->when.time,
  38                    sign, hours, minutes);
  39 }
  40
  41 /** Printing out a blob is simple, get the contents and print */
  42 static void show_blob(const git_blob *blob)
  43 {
  44         /* ? Does this need crlf filtering? */
  45         fwrite(git_blob_rawcontent(blob), (size_t)git_blob_rawsize(blob), 1, stdout);
  46 }
  47
  48 /** Show each entry with its type, id and attributes */
  49 static void show_tree(const git_tree *tree)
  50 {
  51         size_t i, max_i = (int)git_tree_entrycount(tree);
  52         char oidstr[GIT_OID_HEXSZ + 1];
  53         const git_tree_entry *te;
  54
  55         for (i = 0; i < max_i; ++i) {
  56                 te = git_tree_entry_byindex(tree, i);
  57
  58                 git_oid_tostr(oidstr, sizeof(oidstr), git_tree_entry_id(te));
  59
  60                 printf("%06o %s %s\t%s\n",
  61                         git_tree_entry_filemode(te),
  62                         git_object_type2string(git_tree_entry_type(te)),
  63                         oidstr, git_tree_entry_name(te));
  64         }
  65 }
  66
  67 /**
  68  * Commits and tags have a few interesting fields in their header.
  69  */
  70 static void show_commit(const git_commit *commit)
  71 {
  72         unsigned int i, max_i;
  73         char oidstr[GIT_OID_HEXSZ + 1];
  74
  75         git_oid_tostr(oidstr, sizeof(oidstr), git_commit_tree_id(commit));
  76         printf("tree %s\n", oidstr);
  77
  78         max_i = (unsigned int)git_commit_parentcount(commit);
  79         for (i = 0; i < max_i; ++i) {
  80                 git_oid_tostr(oidstr, sizeof(oidstr), git_commit_parent_id(commit, i));
  81                 printf("parent %s\n", oidstr);
  82         }
  83
  84         print_signature("author", git_commit_author(commit));
  85         print_signature("committer", git_commit_committer(commit));
  86
  87         if (git_commit_message(commit))
  88                 printf("\n%s\n", git_commit_message(commit));
  89 }
  90
  91 static void show_tag(const git_tag *tag)
  92 {
  93         char oidstr[GIT_OID_HEXSZ + 1];
  94
  95         git_oid_tostr(oidstr, sizeof(oidstr), git_tag_target_id(tag));;
  96         printf("object %s\n", oidstr);
  97         printf("type %s\n", git_object_type2string(git_tag_target_type(tag)));
  98         printf("tag %s\n", git_tag_name(tag));
  99         print_signature("tagger", git_tag_tagger(tag));
 100
 101         if (git_tag_message(tag))
 102                 printf("\n%s\n", git_tag_message(tag));
 103 }
 104
 105 typedef enum {
 106         SHOW_TYPE = 1,
 107         SHOW_SIZE = 2,
 108         SHOW_NONE = 3,
 109         SHOW_PRETTY = 4
 110 } catfile_mode;
 111
 112 /* Forward declarations for option-parsing helper */
 113 struct catfile_options {
 114         const char *dir;
 115         const char *rev;
 116         catfile_mode action;
 117         int verbose;
 118 };
 119
 120 static void parse_opts(struct catfile_options *o, int argc, char *argv[]);
 121
 122
 123 /** Entry point for this command */
 124 int lg2_cat_file(git_repository *repo, int argc, char *argv[])
 125 {
 126         struct catfile_options o = { ".", NULL, 0, 0 };
 127         git_object *obj = NULL;
 128         char oidstr[GIT_OID_HEXSZ + 1];
 129
 130         parse_opts(&o, argc, argv);
 131
 132         check_lg2(git_revparse_single(&obj, repo, o.rev),
 133                         "Could not resolve", o.rev);
 134
 135         if (o.verbose) {
 136                 char oidstr[GIT_OID_HEXSZ + 1];
 137                 git_oid_tostr(oidstr, sizeof(oidstr), git_object_id(obj));
 138
 139                 printf("%s %s\n--\n",
 140                         git_object_type2string(git_object_type(obj)), oidstr);
 141         }
 142
 143         switch (o.action) {
 144         case SHOW_TYPE:
 145                 printf("%s\n", git_object_type2string(git_object_type(obj)));
 146                 break;
 147         case SHOW_SIZE: {
 148                 git_odb *odb;
 149                 git_odb_object *odbobj;
 150
 151                 check_lg2(git_repository_odb(&odb, repo), "Could not open ODB", NULL);
 152                 check_lg2(git_odb_read(&odbobj, odb, git_object_id(obj)),
 153                         "Could not find obj", NULL);
 154
 155                 printf("%ld\n", (long)git_odb_object_size(odbobj));
 156
 157                 git_odb_object_free(odbobj);
 158                 git_odb_free(odb);
 159                 }
 160                 break;
 161         case SHOW_NONE:
 162                 /* just want return result */
 163                 break;
 164         case SHOW_PRETTY:
 165
 166                 switch (git_object_type(obj)) {
 167                 case GIT_OBJECT_BLOB:
 168                         show_blob((const git_blob *)obj);
 169                         break;
 170                 case GIT_OBJECT_COMMIT:
 171                         show_commit((const git_commit *)obj);
 172                         break;
 173                 case GIT_OBJECT_TREE:
 174                         show_tree((const git_tree *)obj);
 175                         break;
 176                 case GIT_OBJECT_TAG:
 177                         show_tag((const git_tag *)obj);
 178                         break;
 179                 default:
 180                         printf("unknown %s\n", oidstr);
 181                         break;
 182                 }
 183                 break;
 184         }
 185
 186         git_object_free(obj);
 187
 188         return 0;
 189 }
 190
 191 /** Print out usage information */
 192 static void usage(const char *message, const char *arg)
 193 {
 194         if (message && arg)
 195                 fprintf(stderr, "%s: %s\n", message, arg);
 196         else if (message)
 197                 fprintf(stderr, "%s\n", message);
 198         fprintf(stderr,
 199                         "usage: cat-file (-t | -s | -e | -p) [-v] [-q] "
 200                         "[-h|--help] [--git-dir=<dir>] <object>\n");
 201         exit(1);
 202 }
 203
 204 /** Parse the command-line options taken from git */
 205 static void parse_opts(struct catfile_options *o, int argc, char *argv[])
 206 {
 207         struct args_info args = ARGS_INFO_INIT;
 208
 209         for (args.pos = 1; args.pos < argc; ++args.pos) {
 210                 char *a = argv[args.pos];
 211
 212                 if (a[0] != '-') {
 213                         if (o->rev != NULL)
 214                                 usage("Only one rev should be provided", NULL);
 215                         else
 216                                 o->rev = a;
 217                 }
 218                 else if (!strcmp(a, "-t"))
 219                         o->action = SHOW_TYPE;
 220                 else if (!strcmp(a, "-s"))
 221                         o->action = SHOW_SIZE;
 222                 else if (!strcmp(a, "-e"))
 223                         o->action = SHOW_NONE;
 224                 else if (!strcmp(a, "-p"))
 225                         o->action = SHOW_PRETTY;
 226                 else if (!strcmp(a, "-q"))
 227                         o->verbose = 0;
 228                 else if (!strcmp(a, "-v"))
 229                         o->verbose = 1;
 230                 else if (!strcmp(a, "--help") || !strcmp(a, "-h"))
 231                         usage(NULL, NULL);
 232                 else if (!match_str_arg(&o->dir, &args, "--git-dir"))
 233                         usage("Unknown option", a);
 234         }
 235
 236         if (!o->action || !o->rev)
 237                 usage(NULL, NULL);
 238
 239 }