builtin-cat-file.con commit gitweb: Secure against commit-ish/tree-ish with the same name as path (45bd0c8)
   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
  12static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
  13{
  14        /* the parser in tag.c is useless here. */
  15        const char *endp = buf + size;
  16        const char *cp = buf;
  17
  18        while (cp < endp) {
  19                char c = *cp++;
  20                if (c != '\n')
  21                        continue;
  22                if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
  23                        const char *tagger = cp;
  24
  25                        /* Found the tagger line.  Copy out the contents
  26                         * of the buffer so far.
  27                         */
  28                        write_or_die(1, buf, cp - buf);
  29
  30                        /*
  31                         * Do something intelligent, like pretty-printing
  32                         * the date.
  33                         */
  34                        while (cp < endp) {
  35                                if (*cp++ == '\n') {
  36                                        /* tagger to cp is a line
  37                                         * that has ident and time.
  38                                         */
  39                                        const char *sp = tagger;
  40                                        char *ep;
  41                                        unsigned long date;
  42                                        long tz;
  43                                        while (sp < cp && *sp != '>')
  44                                                sp++;
  45                                        if (sp == cp) {
  46                                                /* give up */
  47                                                write_or_die(1, tagger,
  48                                                             cp - tagger);
  49                                                break;
  50                                        }
  51                                        while (sp < cp &&
  52                                               !('0' <= *sp && *sp <= '9'))
  53                                                sp++;
  54                                        write_or_die(1, tagger, sp - tagger);
  55                                        date = strtoul(sp, &ep, 10);
  56                                        tz = strtol(ep, NULL, 10);
  57                                        sp = show_date(date, tz, 0);
  58                                        write_or_die(1, sp, strlen(sp));
  59                                        xwrite(1, "\n", 1);
  60                                        break;
  61                                }
  62                        }
  63                        break;
  64                }
  65                if (cp < endp && *cp == '\n')
  66                        /* end of header */
  67                        break;
  68        }
  69        /* At this point, we have copied out the header up to the end of
  70         * the tagger line and cp points at one past \n.  It could be the
  71         * next header line after the tagger line, or it could be another
  72         * \n that marks the end of the headers.  We need to copy out the
  73         * remainder as is.
  74         */
  75        if (cp < endp)
  76                write_or_die(1, cp, endp - cp);
  77}
  78
  79int cmd_cat_file(int argc, const char **argv, const char *prefix)
  80{
  81        unsigned char sha1[20];
  82        char type[20];
  83        void *buf;
  84        unsigned long size;
  85        int opt;
  86
  87        git_config(git_default_config);
  88        if (argc != 3)
  89                usage("git-cat-file [-t|-s|-e|-p|<type>] <sha1>");
  90        if (get_sha1(argv[2], sha1))
  91                die("Not a valid object name %s", argv[2]);
  92
  93        opt = 0;
  94        if ( argv[1][0] == '-' ) {
  95                opt = argv[1][1];
  96                if ( !opt || argv[1][2] )
  97                        opt = -1; /* Not a single character option */
  98        }
  99
 100        buf = NULL;
 101        switch (opt) {
 102        case 't':
 103                if (!sha1_object_info(sha1, type, NULL)) {
 104                        printf("%s\n", type);
 105                        return 0;
 106                }
 107                break;
 108
 109        case 's':
 110                if (!sha1_object_info(sha1, type, &size)) {
 111                        printf("%lu\n", size);
 112                        return 0;
 113                }
 114                break;
 115
 116        case 'e':
 117                return !has_sha1_file(sha1);
 118
 119        case 'p':
 120                if (sha1_object_info(sha1, type, NULL))
 121                        die("Not a valid object name %s", argv[2]);
 122
 123                /* custom pretty-print here */
 124                if (!strcmp(type, tree_type))
 125                        return cmd_ls_tree(2, argv + 1, NULL);
 126
 127                buf = read_sha1_file(sha1, type, &size);
 128                if (!buf)
 129                        die("Cannot read object %s", argv[2]);
 130                if (!strcmp(type, tag_type)) {
 131                        pprint_tag(sha1, buf, size);
 132                        return 0;
 133                }
 134
 135                /* otherwise just spit out the data */
 136                break;
 137        case 0:
 138                buf = read_object_with_reference(sha1, argv[1], &size, NULL);
 139                break;
 140
 141        default:
 142                die("git-cat-file: unknown option: %s\n", argv[1]);
 143        }
 144
 145        if (!buf)
 146                die("git-cat-file %s: bad file", argv[2]);
 147
 148        write_or_die(1, buf, size);
 149        return 0;
 150}