builtin / cat-file.con commit apply: document buffer ownership rules across functions (92737a2)
   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
  15#define BATCH 1
  16#define BATCH_CHECK 2
  17
  18static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
  19{
  20        /* the parser in tag.c is useless here. */
  21        const char *endp = buf + size;
  22        const char *cp = buf;
  23
  24        while (cp < endp) {
  25                char c = *cp++;
  26                if (c != '\n')
  27                        continue;
  28                if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
  29                        const char *tagger = cp;
  30
  31                        /* Found the tagger line.  Copy out the contents
  32                         * of the buffer so far.
  33                         */
  34                        write_or_die(1, buf, cp - buf);
  35
  36                        /*
  37                         * Do something intelligent, like pretty-printing
  38                         * the date.
  39                         */
  40                        while (cp < endp) {
  41                                if (*cp++ == '\n') {
  42                                        /* tagger to cp is a line
  43                                         * that has ident and time.
  44                                         */
  45                                        const char *sp = tagger;
  46                                        char *ep;
  47                                        unsigned long date;
  48                                        long tz;
  49                                        while (sp < cp && *sp != '>')
  50                                                sp++;
  51                                        if (sp == cp) {
  52                                                /* give up */
  53                                                write_or_die(1, tagger,
  54                                                             cp - tagger);
  55                                                break;
  56                                        }
  57                                        while (sp < cp &&
  58                                               !('0' <= *sp && *sp <= '9'))
  59                                                sp++;
  60                                        write_or_die(1, tagger, sp - tagger);
  61                                        date = strtoul(sp, &ep, 10);
  62                                        tz = strtol(ep, NULL, 10);
  63                                        sp = show_date(date, tz, 0);
  64                                        write_or_die(1, sp, strlen(sp));
  65                                        xwrite(1, "\n", 1);
  66                                        break;
  67                                }
  68                        }
  69                        break;
  70                }
  71                if (cp < endp && *cp == '\n')
  72                        /* end of header */
  73                        break;
  74        }
  75        /* At this point, we have copied out the header up to the end of
  76         * the tagger line and cp points at one past \n.  It could be the
  77         * next header line after the tagger line, or it could be another
  78         * \n that marks the end of the headers.  We need to copy out the
  79         * remainder as is.
  80         */
  81        if (cp < endp)
  82                write_or_die(1, cp, endp - cp);
  83}
  84
  85static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
  86{
  87        unsigned char sha1[20];
  88        enum object_type type;
  89        char *buf;
  90        unsigned long size;
  91        struct object_context obj_context;
  92
  93        if (get_sha1_with_context(obj_name, sha1, &obj_context))
  94                die("Not a valid object name %s", obj_name);
  95
  96        buf = NULL;
  97        switch (opt) {
  98        case 't':
  99                type = sha1_object_info(sha1, NULL);
 100                if (type > 0) {
 101                        printf("%s\n", typename(type));
 102                        return 0;
 103                }
 104                break;
 105
 106        case 's':
 107                type = sha1_object_info(sha1, &size);
 108                if (type > 0) {
 109                        printf("%lu\n", size);
 110                        return 0;
 111                }
 112                break;
 113
 114        case 'e':
 115                return !has_sha1_file(sha1);
 116
 117        case 'p':
 118                type = sha1_object_info(sha1, NULL);
 119                if (type < 0)
 120                        die("Not a valid object name %s", obj_name);
 121
 122                /* custom pretty-print here */
 123                if (type == OBJ_TREE) {
 124                        const char *ls_args[3] = { NULL };
 125                        ls_args[0] =  "ls-tree";
 126                        ls_args[1] =  obj_name;
 127                        return cmd_ls_tree(2, ls_args, NULL);
 128                }
 129
 130                buf = read_sha1_file(sha1, &type, &size);
 131                if (!buf)
 132                        die("Cannot read object %s", obj_name);
 133                if (type == OBJ_TAG) {
 134                        pprint_tag(sha1, buf, size);
 135                        return 0;
 136                }
 137
 138                /* otherwise just spit out the data */
 139                break;
 140
 141        case 'c':
 142                if (!obj_context.path[0])
 143                        die("git cat-file --textconv %s: <object> must be <sha1:path>",
 144                            obj_name);
 145
 146                if (!textconv_object(obj_context.path, obj_context.mode, sha1, &buf, &size))
 147                        die("git cat-file --textconv: unable to run textconv on %s",
 148                            obj_name);
 149                break;
 150
 151        case 0:
 152                buf = read_object_with_reference(sha1, exp_type, &size, NULL);
 153                break;
 154
 155        default:
 156                die("git cat-file: unknown option: %s", exp_type);
 157        }
 158
 159        if (!buf)
 160                die("git cat-file %s: bad file", obj_name);
 161
 162        write_or_die(1, buf, size);
 163        return 0;
 164}
 165
 166static int batch_one_object(const char *obj_name, int print_contents)
 167{
 168        unsigned char sha1[20];
 169        enum object_type type = 0;
 170        unsigned long size;
 171        void *contents = contents;
 172
 173        if (!obj_name)
 174           return 1;
 175
 176        if (get_sha1(obj_name, sha1)) {
 177                printf("%s missing\n", obj_name);
 178                fflush(stdout);
 179                return 0;
 180        }
 181
 182        if (print_contents == BATCH)
 183                contents = read_sha1_file(sha1, &type, &size);
 184        else
 185                type = sha1_object_info(sha1, &size);
 186
 187        if (type <= 0) {
 188                printf("%s missing\n", obj_name);
 189                fflush(stdout);
 190                if (print_contents == BATCH)
 191                        free(contents);
 192                return 0;
 193        }
 194
 195        printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
 196        fflush(stdout);
 197
 198        if (print_contents == BATCH) {
 199                write_or_die(1, contents, size);
 200                printf("\n");
 201                fflush(stdout);
 202                free(contents);
 203        }
 204
 205        return 0;
 206}
 207
 208static int batch_objects(int print_contents)
 209{
 210        struct strbuf buf = STRBUF_INIT;
 211
 212        while (strbuf_getline(&buf, stdin, '\n') != EOF) {
 213                int error = batch_one_object(buf.buf, print_contents);
 214                if (error)
 215                        return error;
 216        }
 217
 218        return 0;
 219}
 220
 221static const char * const cat_file_usage[] = {
 222        "git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>",
 223        "git cat-file (--batch|--batch-check) < <list_of_objects>",
 224        NULL
 225};
 226
 227static int git_cat_file_config(const char *var, const char *value, void *cb)
 228{
 229        switch (userdiff_config(var, value)) {
 230        case 0:
 231                break;
 232        case -1:
 233                return -1;
 234        default:
 235                return 0;
 236        }
 237
 238        return git_default_config(var, value, cb);
 239}
 240
 241int cmd_cat_file(int argc, const char **argv, const char *prefix)
 242{
 243        int opt = 0, batch = 0;
 244        const char *exp_type = NULL, *obj_name = NULL;
 245
 246        const struct option options[] = {
 247                OPT_GROUP("<type> can be one of: blob, tree, commit, tag"),
 248                OPT_SET_INT('t', NULL, &opt, "show object type", 't'),
 249                OPT_SET_INT('s', NULL, &opt, "show object size", 's'),
 250                OPT_SET_INT('e', NULL, &opt,
 251                            "exit with zero when there's no error", 'e'),
 252                OPT_SET_INT('p', NULL, &opt, "pretty-print object's content", 'p'),
 253                OPT_SET_INT(0, "textconv", &opt,
 254                            "for blob objects, run textconv on object's content", 'c'),
 255                OPT_SET_INT(0, "batch", &batch,
 256                            "show info and content of objects fed from the standard input",
 257                            BATCH),
 258                OPT_SET_INT(0, "batch-check", &batch,
 259                            "show info about objects fed from the standard input",
 260                            BATCH_CHECK),
 261                OPT_END()
 262        };
 263
 264        git_config(git_cat_file_config, NULL);
 265
 266        if (argc != 3 && argc != 2)
 267                usage_with_options(cat_file_usage, options);
 268
 269        argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 270
 271        if (opt) {
 272                if (argc == 1)
 273                        obj_name = argv[0];
 274                else
 275                        usage_with_options(cat_file_usage, options);
 276        }
 277        if (!opt && !batch) {
 278                if (argc == 2) {
 279                        exp_type = argv[0];
 280                        obj_name = argv[1];
 281                } else
 282                        usage_with_options(cat_file_usage, options);
 283        }
 284        if (batch && (opt || argc)) {
 285                usage_with_options(cat_file_usage, options);
 286        }
 287
 288        if (batch)
 289                return batch_objects(batch);
 290
 291        return cat_one_file(opt, exp_type, obj_name);
 292}