Andrew's git - gitweb.git/blob - 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
  16static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
  17{
  18        unsigned char sha1[20];
  19        enum object_type type;
  20        char *buf;
  21        unsigned long size;
  22        struct object_context obj_context;
  23
  24        if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
  25                die("Not a valid object name %s", obj_name);
  26
  27        buf = NULL;
  28        switch (opt) {
  29        case 't':
  30                type = sha1_object_info(sha1, NULL);
  31                if (type > 0) {
  32                        printf("%s\n", typename(type));
  33                        return 0;
  34                }
  35                break;
  36
  37        case 's':
  38                type = sha1_object_info(sha1, &size);
  39                if (type > 0) {
  40                        printf("%lu\n", size);
  41                        return 0;
  42                }
  43                break;
  44
  45        case 'e':
  46                return !has_sha1_file(sha1);
  47
  48        case 'p':
  49                type = sha1_object_info(sha1, NULL);
  50                if (type < 0)
  51                        die("Not a valid object name %s", obj_name);
  52
  53                /* custom pretty-print here */
  54                if (type == OBJ_TREE) {
  55                        const char *ls_args[3] = { NULL };
  56                        ls_args[0] =  "ls-tree";
  57                        ls_args[1] =  obj_name;
  58                        return cmd_ls_tree(2, ls_args, NULL);
  59                }
  60
  61                if (type == OBJ_BLOB)
  62                        return stream_blob_to_fd(1, sha1, NULL, 0);
  63                buf = read_sha1_file(sha1, &type, &size);
  64                if (!buf)
  65                        die("Cannot read object %s", obj_name);
  66
  67                /* otherwise just spit out the data */
  68                break;
  69
  70        case 'c':
  71                if (!obj_context.path[0])
  72                        die("git cat-file --textconv %s: <object> must be <sha1:path>",
  73                            obj_name);
  74
  75                if (!textconv_object(obj_context.path, obj_context.mode, sha1, 1, &buf, &size))
  76                        die("git cat-file --textconv: unable to run textconv on %s",
  77                            obj_name);
  78                break;
  79
  80        case 0:
  81                if (type_from_string(exp_type) == OBJ_BLOB) {
  82                        unsigned char blob_sha1[20];
  83                        if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
  84                                enum object_type type;
  85                                unsigned long size;
  86                                char *buffer = read_sha1_file(sha1, &type, &size);
  87                                if (memcmp(buffer, "object ", 7) ||
  88                                    get_sha1_hex(buffer + 7, blob_sha1))
  89                                        die("%s not a valid tag", sha1_to_hex(sha1));
  90                                free(buffer);
  91                        } else
  92                                hashcpy(blob_sha1, sha1);
  93
  94                        if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
  95                                return stream_blob_to_fd(1, blob_sha1, NULL, 0);
  96                        /*
  97                         * we attempted to dereference a tag to a blob
  98                         * and failed; there may be new dereference
  99                         * mechanisms this code is not aware of.
 100                         * fall-back to the usual case.
 101                         */
 102                }
 103                buf = read_object_with_reference(sha1, exp_type, &size, NULL);
 104                break;
 105
 106        default:
 107                die("git cat-file: unknown option: %s", exp_type);
 108        }
 109
 110        if (!buf)
 111                die("git cat-file %s: bad file", obj_name);
 112
 113        write_or_die(1, buf, size);
 114        return 0;
 115}
 116
 117static void print_object_or_die(int fd, const unsigned char *sha1,
 118                                enum object_type type, unsigned long size)
 119{
 120        if (type == OBJ_BLOB) {
 121                if (stream_blob_to_fd(fd, sha1, NULL, 0) < 0)
 122                        die("unable to stream %s to stdout", sha1_to_hex(sha1));
 123        }
 124        else {
 125                enum object_type rtype;
 126                unsigned long rsize;
 127                void *contents;
 128
 129                contents = read_sha1_file(sha1, &rtype, &rsize);
 130                if (!contents)
 131                        die("object %s disappeared", sha1_to_hex(sha1));
 132                if (rtype != type)
 133                        die("object %s changed type!?", sha1_to_hex(sha1));
 134                if (rsize != size)
 135                        die("object %s change size!?", sha1_to_hex(sha1));
 136
 137                write_or_die(fd, contents, size);
 138                free(contents);
 139        }
 140}
 141
 142struct batch_options {
 143        int enabled;
 144        int print_contents;
 145};
 146
 147static int batch_one_object(const char *obj_name, struct batch_options *opt)
 148{
 149        unsigned char sha1[20];
 150        enum object_type type = 0;
 151        unsigned long size;
 152
 153        if (!obj_name)
 154           return 1;
 155
 156        if (get_sha1(obj_name, sha1)) {
 157                printf("%s missing\n", obj_name);
 158                fflush(stdout);
 159                return 0;
 160        }
 161
 162        type = sha1_object_info(sha1, &size);
 163        if (type <= 0) {
 164                printf("%s missing\n", obj_name);
 165                fflush(stdout);
 166                return 0;
 167        }
 168
 169        printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
 170        fflush(stdout);
 171
 172        if (opt->print_contents) {
 173                print_object_or_die(1, sha1, type, size);
 174                write_or_die(1, "\n", 1);
 175        }
 176        return 0;
 177}
 178
 179static int batch_objects(struct batch_options *opt)
 180{
 181        struct strbuf buf = STRBUF_INIT;
 182
 183        while (strbuf_getline(&buf, stdin, '\n') != EOF) {
 184                int error = batch_one_object(buf.buf, opt);
 185                if (error)
 186                        return error;
 187        }
 188
 189        return 0;
 190}
 191
 192static const char * const cat_file_usage[] = {
 193        N_("git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>"),
 194        N_("git cat-file (--batch|--batch-check) < <list_of_objects>"),
 195        NULL
 196};
 197
 198static int git_cat_file_config(const char *var, const char *value, void *cb)
 199{
 200        if (userdiff_config(var, value) < 0)
 201                return -1;
 202
 203        return git_default_config(var, value, cb);
 204}
 205
 206static int batch_option_callback(const struct option *opt,
 207                                 const char *arg,
 208                                 int unset)
 209{
 210        struct batch_options *bo = opt->value;
 211
 212        if (unset) {
 213                memset(bo, 0, sizeof(*bo));
 214                return 0;
 215        }
 216
 217        bo->enabled = 1;
 218        bo->print_contents = !strcmp(opt->long_name, "batch");
 219
 220        return 0;
 221}
 222
 223int cmd_cat_file(int argc, const char **argv, const char *prefix)
 224{
 225        int opt = 0;
 226        const char *exp_type = NULL, *obj_name = NULL;
 227        struct batch_options batch = {0};
 228
 229        const struct option options[] = {
 230                OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
 231                OPT_SET_INT('t', NULL, &opt, N_("show object type"), 't'),
 232                OPT_SET_INT('s', NULL, &opt, N_("show object size"), 's'),
 233                OPT_SET_INT('e', NULL, &opt,
 234                            N_("exit with zero when there's no error"), 'e'),
 235                OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
 236                OPT_SET_INT(0, "textconv", &opt,
 237                            N_("for blob objects, run textconv on object's content"), 'c'),
 238                { OPTION_CALLBACK, 0, "batch", &batch, NULL,
 239                        N_("show info and content of objects fed from the standard input"),
 240                        PARSE_OPT_NOARG, batch_option_callback },
 241                { OPTION_CALLBACK, 0, "batch-check", &batch, NULL,
 242                        N_("show info about objects fed from the standard input"),
 243                        PARSE_OPT_NOARG, batch_option_callback },
 244                OPT_END()
 245        };
 246
 247        git_config(git_cat_file_config, NULL);
 248
 249        if (argc != 3 && argc != 2)
 250                usage_with_options(cat_file_usage, options);
 251
 252        argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 253
 254        if (opt) {
 255                if (argc == 1)
 256                        obj_name = argv[0];
 257                else
 258                        usage_with_options(cat_file_usage, options);
 259        }
 260        if (!opt && !batch.enabled) {
 261                if (argc == 2) {
 262                        exp_type = argv[0];
 263                        obj_name = argv[1];
 264                } else
 265                        usage_with_options(cat_file_usage, options);
 266        }
 267        if (batch.enabled && (opt || argc)) {
 268                usage_with_options(cat_file_usage, options);
 269        }
 270
 271        if (batch.enabled)
 272                return batch_objects(&batch);
 273
 274        return cat_one_file(opt, exp_type, obj_name);
 275}