builtin/interpret-trailers.c

   1 /*
   2  * Builtin "git interpret-trailers"
   3  *
   4  * Copyright (c) 2013, 2014 Christian Couder <chriscool@tuxfamily.org>
   5  *
   6  */
   7
   8 #include "builtin.h"
   9 #include "gettext.h"
  10 #include "parse-options.h"
  11 #include "string-list.h"
  12 #include "tempfile.h"
  13 #include "trailer.h"
  14 #include "config.h"
  15
  16 static const char * const git_interpret_trailers_usage[] = {
  17         N_("git interpret-trailers [--in-place] [--trim-empty]\n"
  18            "                       [(--trailer (<key>|<key-alias>)[(=|:)<value>])...]\n"
  19            "                       [--parse] [<file>...]"),
  20         NULL
  21 };
  22
  23 static enum trailer_where where;
  24 static enum trailer_if_exists if_exists;
  25 static enum trailer_if_missing if_missing;
  26
  27 static int option_parse_where(const struct option *opt,
  28                               const char *arg, int unset UNUSED)
  29 {
  30         /* unset implies NULL arg, which is handled in our helper */
  31         return trailer_set_where(opt->value, arg);
  32 }
  33
  34 static int option_parse_if_exists(const struct option *opt,
  35                                   const char *arg, int unset UNUSED)
  36 {
  37         /* unset implies NULL arg, which is handled in our helper */
  38         return trailer_set_if_exists(opt->value, arg);
  39 }
  40
  41 static int option_parse_if_missing(const struct option *opt,
  42                                    const char *arg, int unset UNUSED)
  43 {
  44         /* unset implies NULL arg, which is handled in our helper */
  45         return trailer_set_if_missing(opt->value, arg);
  46 }
  47
  48 static void new_trailers_clear(struct list_head *trailers)
  49 {
  50         struct list_head *pos, *tmp;
  51         struct new_trailer_item *item;
  52
  53         list_for_each_safe(pos, tmp, trailers) {
  54                 item = list_entry(pos, struct new_trailer_item, list);
  55                 list_del(pos);
  56                 free(item);
  57         }
  58 }
  59
  60 static int option_parse_trailer(const struct option *opt,
  61                                    const char *arg, int unset)
  62 {
  63         struct list_head *trailers = opt->value;
  64         struct new_trailer_item *item;
  65
  66         if (unset) {
  67                 new_trailers_clear(trailers);
  68                 return 0;
  69         }
  70
  71         if (!arg)
  72                 return -1;
  73
  74         item = xmalloc(sizeof(*item));
  75         item->text = arg;
  76         item->where = where;
  77         item->if_exists = if_exists;
  78         item->if_missing = if_missing;
  79         list_add_tail(&item->list, trailers);
  80         return 0;
  81 }
  82
  83 static int parse_opt_parse(const struct option *opt, const char *arg,
  84                            int unset)
  85 {
  86         struct process_trailer_options *v = opt->value;
  87         v->only_trailers = 1;
  88         v->only_input = 1;
  89         v->unfold = 1;
  90         BUG_ON_OPT_NEG(unset);
  91         BUG_ON_OPT_ARG(arg);
  92         return 0;
  93 }
  94
  95 static struct tempfile *trailers_tempfile;
  96
  97 static FILE *create_in_place_tempfile(const char *file)
  98 {
  99         struct stat st;
 100         struct strbuf filename_template = STRBUF_INIT;
 101         const char *tail;
 102         FILE *outfile;
 103
 104         if (stat(file, &st))
 105                 die_errno(_("could not stat %s"), file);
 106         if (!S_ISREG(st.st_mode))
 107                 die(_("file %s is not a regular file"), file);
 108         if (!(st.st_mode & S_IWUSR))
 109                 die(_("file %s is not writable by user"), file);
 110
 111         /* Create temporary file in the same directory as the original */
 112         tail = strrchr(file, '/');
 113         if (tail)
 114                 strbuf_add(&filename_template, file, tail - file + 1);
 115         strbuf_addstr(&filename_template, "git-interpret-trailers-XXXXXX");
 116
 117         trailers_tempfile = xmks_tempfile_m(filename_template.buf, st.st_mode);
 118         strbuf_release(&filename_template);
 119         outfile = fdopen_tempfile(trailers_tempfile, "w");
 120         if (!outfile)
 121                 die_errno(_("could not open temporary file"));
 122
 123         return outfile;
 124 }
 125
 126 static void read_input_file(struct strbuf *sb, const char *file)
 127 {
 128         if (file) {
 129                 if (strbuf_read_file(sb, file, 0) < 0)
 130                         die_errno(_("could not read input file '%s'"), file);
 131         } else {
 132                 if (strbuf_read(sb, fileno(stdin), 0) < 0)
 133                         die_errno(_("could not read from stdin"));
 134         }
 135 }
 136
 137 static void interpret_trailers(const struct process_trailer_options *opts,
 138                                struct list_head *new_trailer_head,
 139                                const char *file)
 140 {
 141         LIST_HEAD(head);
 142         struct strbuf sb = STRBUF_INIT;
 143         struct strbuf trailer_block = STRBUF_INIT;
 144         struct trailer_info info;
 145         FILE *outfile = stdout;
 146
 147         trailer_config_init();
 148
 149         read_input_file(&sb, file);
 150
 151         if (opts->in_place)
 152                 outfile = create_in_place_tempfile(file);
 153
 154         parse_trailers(opts, &info, sb.buf, &head);
 155
 156         /* Print the lines before the trailers */
 157         if (!opts->only_trailers)
 158                 fwrite(sb.buf, 1, info.trailer_block_start, outfile);
 159
 160         if (!opts->only_trailers && !info.blank_line_before_trailer)
 161                 fprintf(outfile, "\n");
 162
 163
 164         if (!opts->only_input) {
 165                 LIST_HEAD(config_head);
 166                 LIST_HEAD(arg_head);
 167                 parse_trailers_from_config(&config_head);
 168                 parse_trailers_from_command_line_args(&arg_head, new_trailer_head);
 169                 list_splice(&config_head, &arg_head);
 170                 process_trailers_lists(&head, &arg_head);
 171         }
 172
 173         /* Print trailer block. */
 174         format_trailers(opts, &head, &trailer_block);
 175         free_trailers(&head);
 176         fwrite(trailer_block.buf, 1, trailer_block.len, outfile);
 177         strbuf_release(&trailer_block);
 178
 179         /* Print the lines after the trailers as is */
 180         if (!opts->only_trailers)
 181                 fwrite(sb.buf + info.trailer_block_end, 1, sb.len - info.trailer_block_end, outfile);
 182         trailer_info_release(&info);
 183
 184         if (opts->in_place)
 185                 if (rename_tempfile(&trailers_tempfile, file))
 186                         die_errno(_("could not rename temporary file to %s"), file);
 187
 188         strbuf_release(&sb);
 189 }
 190
 191 int cmd_interpret_trailers(int argc, const char **argv, const char *prefix)
 192 {
 193         struct process_trailer_options opts = PROCESS_TRAILER_OPTIONS_INIT;
 194         LIST_HEAD(trailers);
 195
 196         struct option options[] = {
 197                 OPT_BOOL(0, "in-place", &opts.in_place, N_("edit files in place")),
 198                 OPT_BOOL(0, "trim-empty", &opts.trim_empty, N_("trim empty trailers")),
 199
 200                 OPT_CALLBACK(0, "where", &where, N_("placement"),
 201                              N_("where to place the new trailer"), option_parse_where),
 202                 OPT_CALLBACK(0, "if-exists", &if_exists, N_("action"),
 203                              N_("action if trailer already exists"), option_parse_if_exists),
 204                 OPT_CALLBACK(0, "if-missing", &if_missing, N_("action"),
 205                              N_("action if trailer is missing"), option_parse_if_missing),
 206
 207                 OPT_BOOL(0, "only-trailers", &opts.only_trailers, N_("output only the trailers")),
 208                 OPT_BOOL(0, "only-input", &opts.only_input, N_("do not apply trailer.* configuration variables")),
 209                 OPT_BOOL(0, "unfold", &opts.unfold, N_("reformat multiline trailer values as single-line values")),
 210                 OPT_CALLBACK_F(0, "parse", &opts, NULL, N_("alias for --only-trailers --only-input --unfold"),
 211                         PARSE_OPT_NOARG | PARSE_OPT_NONEG, parse_opt_parse),
 212                 OPT_BOOL(0, "no-divider", &opts.no_divider, N_("do not treat \"---\" as the end of input")),
 213                 OPT_CALLBACK(0, "trailer", &trailers, N_("trailer"),
 214                                 N_("trailer(s) to add"), option_parse_trailer),
 215                 OPT_END()
 216         };
 217
 218         git_config(git_default_config, NULL);
 219
 220         argc = parse_options(argc, argv, prefix, options,
 221                              git_interpret_trailers_usage, 0);
 222
 223         if (opts.only_input && !list_empty(&trailers))
 224                 usage_msg_opt(
 225                         _("--trailer with --only-input does not make sense"),
 226                         git_interpret_trailers_usage,
 227                         options);
 228
 229         if (argc) {
 230                 int i;
 231                 for (i = 0; i < argc; i++)
 232                         interpret_trailers(&opts, &trailers, argv[i]);
 233         } else {
 234                 if (opts.in_place)
 235                         die(_("no input file given for in-place editing"));
 236                 interpret_trailers(&opts, &trailers, NULL);
 237         }
 238
 239         new_trailers_clear(&trailers);
 240
 241         return 0;
 242 }