builtin/hash-object.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  * Copyright (C) Junio C Hamano, 2005
   6  */
   7 #include "builtin.h"
   8 #include "abspath.h"
   9 #include "config.h"
  10 #include "gettext.h"
  11 #include "hex.h"
  12 #include "object-file.h"
  13 #include "object-store-ll.h"
  14 #include "blob.h"
  15 #include "quote.h"
  16 #include "parse-options.h"
  17 #include "exec-cmd.h"
  18 #include "setup.h"
  19 #include "strbuf.h"
  20 #include "write-or-die.h"
  21
  22 /*
  23  * This is to create corrupt objects for debugging and as such it
  24  * needs to bypass the data conversion performed by, and the type
  25  * limitation imposed by, index_fd() and its callees.
  26  */
  27 static int hash_literally(struct object_id *oid, int fd, const char *type, unsigned flags)
  28 {
  29         struct strbuf buf = STRBUF_INIT;
  30         int ret;
  31
  32         if (strbuf_read(&buf, fd, 4096) < 0)
  33                 ret = -1;
  34         else
  35                 ret = write_object_file_literally(buf.buf, buf.len, type, oid,
  36                                                  flags);
  37         close(fd);
  38         strbuf_release(&buf);
  39         return ret;
  40 }
  41
  42 static void hash_fd(int fd, const char *type, const char *path, unsigned flags,
  43                     int literally)
  44 {
  45         struct stat st;
  46         struct object_id oid;
  47
  48         if (fstat(fd, &st) < 0 ||
  49             (literally
  50              ? hash_literally(&oid, fd, type, flags)
  51              : index_fd(the_repository->index, &oid, fd, &st,
  52                         type_from_string(type), path, flags)))
  53                 die((flags & HASH_WRITE_OBJECT)
  54                     ? "Unable to add %s to database"
  55                     : "Unable to hash %s", path);
  56         printf("%s\n", oid_to_hex(&oid));
  57         maybe_flush_or_die(stdout, "hash to stdout");
  58 }
  59
  60 static void hash_object(const char *path, const char *type, const char *vpath,
  61                         unsigned flags, int literally)
  62 {
  63         int fd;
  64         fd = xopen(path, O_RDONLY);
  65         hash_fd(fd, type, vpath, flags, literally);
  66 }
  67
  68 static void hash_stdin_paths(const char *type, int no_filters, unsigned flags,
  69                              int literally)
  70 {
  71         struct strbuf buf = STRBUF_INIT;
  72         struct strbuf unquoted = STRBUF_INIT;
  73
  74         while (strbuf_getline(&buf, stdin) != EOF) {
  75                 if (buf.buf[0] == '"') {
  76                         strbuf_reset(&unquoted);
  77                         if (unquote_c_style(&unquoted, buf.buf, NULL))
  78                                 die("line is badly quoted");
  79                         strbuf_swap(&buf, &unquoted);
  80                 }
  81                 hash_object(buf.buf, type, no_filters ? NULL : buf.buf, flags,
  82                             literally);
  83         }
  84         strbuf_release(&buf);
  85         strbuf_release(&unquoted);
  86 }
  87
  88 int cmd_hash_object(int argc, const char **argv, const char *prefix)
  89 {
  90         static const char * const hash_object_usage[] = {
  91                 N_("git hash-object [-t <type>] [-w] [--path=<file> | --no-filters]\n"
  92                    "                [--stdin [--literally]] [--] <file>..."),
  93                 N_("git hash-object [-t <type>] [-w] --stdin-paths [--no-filters]"),
  94                 NULL
  95         };
  96         const char *type = blob_type;
  97         int hashstdin = 0;
  98         int stdin_paths = 0;
  99         int no_filters = 0;
 100         int literally = 0;
 101         int nongit = 0;
 102         unsigned flags = HASH_FORMAT_CHECK;
 103         const char *vpath = NULL;
 104         char *vpath_free = NULL;
 105         const struct option hash_object_options[] = {
 106                 OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
 107                 OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
 108                         HASH_WRITE_OBJECT),
 109                 OPT_COUNTUP( 0 , "stdin", &hashstdin, N_("read the object from stdin")),
 110                 OPT_BOOL( 0 , "stdin-paths", &stdin_paths, N_("read file names from stdin")),
 111                 OPT_BOOL( 0 , "no-filters", &no_filters, N_("store file as is without filters")),
 112                 OPT_BOOL( 0, "literally", &literally, N_("just hash any random garbage to create corrupt objects for debugging Git")),
 113                 OPT_STRING( 0 , "path", &vpath, N_("file"), N_("process file as it were from this path")),
 114                 OPT_END()
 115         };
 116         int i;
 117         const char *errstr = NULL;
 118
 119         argc = parse_options(argc, argv, prefix, hash_object_options,
 120                              hash_object_usage, 0);
 121
 122         if (flags & HASH_WRITE_OBJECT)
 123                 prefix = setup_git_directory();
 124         else
 125                 prefix = setup_git_directory_gently(&nongit);
 126
 127         if (vpath && prefix) {
 128                 vpath_free = prefix_filename(prefix, vpath);
 129                 vpath = vpath_free;
 130         }
 131
 132         git_config(git_default_config, NULL);
 133
 134         if (stdin_paths) {
 135                 if (hashstdin)
 136                         errstr = "Can't use --stdin-paths with --stdin";
 137                 else if (argc)
 138                         errstr = "Can't specify files with --stdin-paths";
 139                 else if (vpath)
 140                         errstr = "Can't use --stdin-paths with --path";
 141         }
 142         else {
 143                 if (hashstdin > 1)
 144                         errstr = "Multiple --stdin arguments are not supported";
 145                 if (vpath && no_filters)
 146                         errstr = "Can't use --path with --no-filters";
 147         }
 148
 149         if (errstr) {
 150                 error("%s", errstr);
 151                 usage_with_options(hash_object_usage, hash_object_options);
 152         }
 153
 154         if (hashstdin)
 155                 hash_fd(0, type, vpath, flags, literally);
 156
 157         for (i = 0 ; i < argc; i++) {
 158                 const char *arg = argv[i];
 159                 char *to_free = NULL;
 160
 161                 if (prefix)
 162                         arg = to_free = prefix_filename(prefix, arg);
 163                 hash_object(arg, type, no_filters ? NULL : vpath ? vpath : arg,
 164                             flags, literally);
 165                 free(to_free);
 166         }
 167
 168         if (stdin_paths)
 169                 hash_stdin_paths(type, no_filters, flags, literally);
 170
 171         free(vpath_free);
 172
 173         return 0;
 174 }