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