70dd8c8a101e04a409d25b535a4968a7935ef81d
   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
  19static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
  20{
  21        unsigned char sha1[20];
  22        enum object_type type;
  23        char *buf;
  24        unsigned long size;
  25        struct object_context obj_context;
  26
  27        if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
  28                die("Not a valid object name %s", obj_name);
  29
  30        buf = NULL;
  31        switch (opt) {
  32        case 't':
  33                type = sha1_object_info(sha1, NULL);
  34                if (type > 0) {
  35                        printf("%s\n", typename(type));
  36                        return 0;
  37                }
  38                break;
  39
  40        case 's':
  41                type = sha1_object_info(sha1, &size);
  42                if (type > 0) {
  43                        printf("%lu\n", size);
  44                        return 0;
  45                }
  46                break;
  47
  48        case 'e':
  49                return !has_sha1_file(sha1);
  50
  51        case 'p':
  52                type = sha1_object_info(sha1, NULL);
  53                if (type < 0)
  54                        die("Not a valid object name %s", obj_name);
  55
  56                /* custom pretty-print here */
  57                if (type == OBJ_TREE) {
  58                        const char *ls_args[3] = { NULL };
  59                        ls_args[0] =  "ls-tree";
  60                        ls_args[1] =  obj_name;
  61                        return cmd_ls_tree(2, ls_args, NULL);
  62                }
  63
  64                if (type == OBJ_BLOB)
  65                        return stream_blob_to_fd(1, sha1, NULL, 0);
  66                buf = read_sha1_file(sha1, &type, &size);
  67                if (!buf)
  68                        die("Cannot read object %s", obj_name);
  69
  70                /* otherwise just spit out the data */
  71                break;
  72
  73        case 'c':
  74                if (!obj_context.path[0])
  75                        die("git cat-file --textconv %s: <object> must be <sha1:path>",
  76                            obj_name);
  77
  78                if (!textconv_object(obj_context.path, obj_context.mode, sha1, 1, &buf, &size))
  79                        die("git cat-file --textconv: unable to run textconv on %s",
  80                            obj_name);
  81                break;
  82
  83        case 0:
  84                if (type_from_string(exp_type) == OBJ_BLOB) {
  85                        unsigned char blob_sha1[20];
  86                        if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
  87                                enum object_type type;
  88                                unsigned long size;
  89                                char *buffer = read_sha1_file(sha1, &type, &size);
  90                                if (memcmp(buffer, "object ", 7) ||
  91                                    get_sha1_hex(buffer + 7, blob_sha1))
  92                                        die("%s not a valid tag", sha1_to_hex(sha1));
  93                                free(buffer);
  94                        } else
  95                                hashcpy(blob_sha1, sha1);
  96
  97                        if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
  98                                return stream_blob_to_fd(1, blob_sha1, NULL, 0);
  99                        /*
 100                         * we attempted to dereference a tag to a blob
 101                         * and failed; there may be new dereference
 102                         * mechanisms this code is not aware of.
 103                         * fall-back to the usual case.
 104                         */
 105                }
 106                buf = read_object_with_reference(sha1, exp_type, &size, NULL);
 107                break;
 108
 109        default:
 110                die("git cat-file: unknown option: %s", exp_type);
 111        }
 112
 113        if (!buf)
 114                die("git cat-file %s: bad file", obj_name);
 115
 116        write_or_die(1, buf, size);
 117        return 0;
 118}
 119
 120static void print_object_or_die(int fd, const unsigned char *sha1,
 121                                enum object_type type, unsigned long size)
 122{
 123        if (type == OBJ_BLOB) {
 124                if (stream_blob_to_fd(fd, sha1, NULL, 0) < 0)
 125                        die("unable to stream %s to stdout", sha1_to_hex(sha1));
 126        }
 127        else {
 128                enum object_type rtype;
 129                unsigned long rsize;
 130                void *contents;
 131
 132                contents = read_sha1_file(sha1, &rtype, &rsize);
 133                if (!contents)
 134                        die("object %s disappeared", sha1_to_hex(sha1));
 135                if (rtype != type)
 136                        die("object %s changed type!?", sha1_to_hex(sha1));
 137                if (rsize != size)
 138                        die("object %s change size!?", sha1_to_hex(sha1));
 139
 140                write_or_die(fd, contents, size);
 141                free(contents);
 142        }
 143}
 144
 145static int batch_one_object(const char *obj_name, int print_contents)
 146{
 147        unsigned char sha1[20];
 148        enum object_type type = 0;
 149        unsigned long size;
 150
 151        if (!obj_name)
 152           return 1;
 153
 154        if (get_sha1(obj_name, sha1)) {
 155                printf("%s missing\n", obj_name);
 156                fflush(stdout);
 157                return 0;
 158        }
 159
 160        type = sha1_object_info(sha1, &size);
 161        if (type <= 0) {
 162                printf("%s missing\n", obj_name);
 163                fflush(stdout);
 164                return 0;
 165        }
 166
 167        printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
 168        fflush(stdout);
 169
 170        if (print_contents == BATCH) {
 171                print_object_or_die(1, sha1, type, size);
 172                write_or_die(1, "\n", 1);
 173        }
 174        return 0;
 175}
 176
 177static int batch_objects(int print_contents)
 178{
 179        struct strbuf buf = STRBUF_INIT;
 180
 181        while (strbuf_getline(&buf, stdin, '\n') != EOF) {
 182                int error = batch_one_object(buf.buf, print_contents);
 183                if (error)
 184                        return error;
 185        }
 186
 187        return 0;
 188}
 189
 190static const char * const cat_file_usage[] = {
 191        N_("git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>"),
 192        N_("git cat-file (--batch|--batch-check) < <list_of_objects>"),
 193        NULL
 194};
 195
 196static int git_cat_file_config(const char *var, const char *value, void *cb)
 197{
 198        if (userdiff_config(var, value) < 0)
 199                return -1;
 200
 201        return git_default_config(var, value, cb);
 202}
 203
 204int cmd_cat_file(int argc, const char **argv, const char *prefix)
 205{
 206        int opt = 0, batch = 0;
 207        const char *exp_type = NULL, *obj_name = NULL;
 208
 209        const struct option options[] = {
 210                OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
 211                OPT_SET_INT('t', NULL, &opt, N_("show object type"), 't'),
 212                OPT_SET_INT('s', NULL, &opt, N_("show object size"), 's'),
 213                OPT_SET_INT('e', NULL, &opt,
 214                            N_("exit with zero when there's no error"), 'e'),
 215                OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
 216                OPT_SET_INT(0, "textconv", &opt,
 217                            N_("for blob objects, run textconv on object's content"), 'c'),
 218                OPT_SET_INT(0, "batch", &batch,
 219                            N_("show info and content of objects fed from the standard input"),
 220                            BATCH),
 221                OPT_SET_INT(0, "batch-check", &batch,
 222                            N_("show info about objects fed from the standard input"),
 223                            BATCH_CHECK),
 224                OPT_END()
 225        };
 226
 227        git_config(git_cat_file_config, NULL);
 228
 229        if (argc != 3 && argc != 2)
 230                usage_with_options(cat_file_usage, options);
 231
 232        argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 233
 234        if (opt) {
 235                if (argc == 1)
 236                        obj_name = argv[0];
 237                else
 238                        usage_with_options(cat_file_usage, options);
 239        }
 240        if (!opt && !batch) {
 241                if (argc == 2) {
 242                        exp_type = argv[0];
 243                        obj_name = argv[1];
 244                } else
 245                        usage_with_options(cat_file_usage, options);
 246        }
 247        if (batch && (opt || argc)) {
 248                usage_with_options(cat_file_usage, options);
 249        }
 250
 251        if (batch)
 252                return batch_objects(batch);
 253
 254        return cat_one_file(opt, exp_type, obj_name);
 255}