ident.c

   1 /*
   2  * ident.c
   3  *
   4  * create git identifier lines of the form "name <email> date"
   5  *
   6  * Copyright (C) 2005 Linus Torvalds
   7  */
   8 #include "cache.h"
   9
  10 static struct strbuf git_default_name = STRBUF_INIT;
  11 static struct strbuf git_default_email = STRBUF_INIT;
  12 static struct strbuf git_default_date = STRBUF_INIT;
  13 static int default_email_is_bogus;
  14 static int default_name_is_bogus;
  15
  16 #define IDENT_NAME_GIVEN 01
  17 #define IDENT_MAIL_GIVEN 02
  18 #define IDENT_ALL_GIVEN (IDENT_NAME_GIVEN|IDENT_MAIL_GIVEN)
  19 static int committer_ident_explicitly_given;
  20 static int author_ident_explicitly_given;
  21
  22 #ifdef NO_GECOS_IN_PWENT
  23 #define get_gecos(ignored) "&"
  24 #else
  25 #define get_gecos(struct_passwd) ((struct_passwd)->pw_gecos)
  26 #endif
  27
  28 static struct passwd *xgetpwuid_self(int *is_bogus)
  29 {
  30         struct passwd *pw;
  31
  32         errno = 0;
  33         pw = getpwuid(getuid());
  34         if (!pw) {
  35                 static struct passwd fallback;
  36                 fallback.pw_name = "unknown";
  37 #ifndef NO_GECOS_IN_PWENT
  38                 fallback.pw_gecos = "Unknown";
  39 #endif
  40                 pw = &fallback;
  41                 if (is_bogus)
  42                         *is_bogus = 1;
  43         }
  44         return pw;
  45 }
  46
  47 static void copy_gecos(const struct passwd *w, struct strbuf *name)
  48 {
  49         char *src;
  50
  51         /* Traditionally GECOS field had office phone numbers etc, separated
  52          * with commas.  Also & stands for capitalized form of the login name.
  53          */
  54
  55         for (src = get_gecos(w); *src && *src != ','; src++) {
  56                 int ch = *src;
  57                 if (ch != '&')
  58                         strbuf_addch(name, ch);
  59                 else {
  60                         /* Sorry, Mr. McDonald... */
  61                         strbuf_addch(name, toupper(*w->pw_name));
  62                         strbuf_addstr(name, w->pw_name + 1);
  63                 }
  64         }
  65 }
  66
  67 static int add_mailname_host(struct strbuf *buf)
  68 {
  69         FILE *mailname;
  70         struct strbuf mailnamebuf = STRBUF_INIT;
  71
  72         mailname = fopen("/etc/mailname", "r");
  73         if (!mailname) {
  74                 if (errno != ENOENT)
  75                         warning("cannot open /etc/mailname: %s",
  76                                 strerror(errno));
  77                 return -1;
  78         }
  79         if (strbuf_getline(&mailnamebuf, mailname, '\n') == EOF) {
  80                 if (ferror(mailname))
  81                         warning("cannot read /etc/mailname: %s",
  82                                 strerror(errno));
  83                 strbuf_release(&mailnamebuf);
  84                 fclose(mailname);
  85                 return -1;
  86         }
  87         /* success! */
  88         strbuf_addbuf(buf, &mailnamebuf);
  89         strbuf_release(&mailnamebuf);
  90         fclose(mailname);
  91         return 0;
  92 }
  93
  94 static int canonical_name(const char *host, struct strbuf *out)
  95 {
  96         int status = -1;
  97
  98 #ifndef NO_IPV6
  99         struct addrinfo hints, *ai;
 100         memset (&hints, '\0', sizeof (hints));
 101         hints.ai_flags = AI_CANONNAME;
 102         if (!getaddrinfo(host, NULL, &hints, &ai)) {
 103                 if (ai && strchr(ai->ai_canonname, '.')) {
 104                         strbuf_addstr(out, ai->ai_canonname);
 105                         status = 0;
 106                 }
 107                 freeaddrinfo(ai);
 108         }
 109 #else
 110         struct hostent *he = gethostbyname(host);
 111         if (he && strchr(he->h_name, '.')) {
 112                 strbuf_addstr(out, he->h_name);
 113                 status = 0;
 114         }
 115 #endif /* NO_IPV6 */
 116
 117         return status;
 118 }
 119
 120 static void add_domainname(struct strbuf *out, int *is_bogus)
 121 {
 122         char buf[1024];
 123
 124         if (gethostname(buf, sizeof(buf))) {
 125                 warning("cannot get host name: %s", strerror(errno));
 126                 strbuf_addstr(out, "(none)");
 127                 *is_bogus = 1;
 128                 return;
 129         }
 130         if (strchr(buf, '.'))
 131                 strbuf_addstr(out, buf);
 132         else if (canonical_name(buf, out) < 0) {
 133                 strbuf_addf(out, "%s.(none)", buf);
 134                 *is_bogus = 1;
 135         }
 136 }
 137
 138 static void copy_email(const struct passwd *pw, struct strbuf *email,
 139                        int *is_bogus)
 140 {
 141         /*
 142          * Make up a fake email address
 143          * (name + '@' + hostname [+ '.' + domainname])
 144          */
 145         strbuf_addstr(email, pw->pw_name);
 146         strbuf_addch(email, '@');
 147
 148         if (!add_mailname_host(email))
 149                 return; /* read from "/etc/mailname" (Debian) */
 150         add_domainname(email, is_bogus);
 151 }
 152
 153 const char *ident_default_name(void)
 154 {
 155         if (!git_default_name.len) {
 156                 copy_gecos(xgetpwuid_self(&default_name_is_bogus), &git_default_name);
 157                 strbuf_trim(&git_default_name);
 158         }
 159         return git_default_name.buf;
 160 }
 161
 162 const char *ident_default_email(void)
 163 {
 164         if (!git_default_email.len) {
 165                 const char *email = getenv("EMAIL");
 166
 167                 if (email && email[0]) {
 168                         strbuf_addstr(&git_default_email, email);
 169                         committer_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 170                         author_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 171                 } else
 172                         copy_email(xgetpwuid_self(&default_email_is_bogus),
 173                                    &git_default_email, &default_email_is_bogus);
 174                 strbuf_trim(&git_default_email);
 175         }
 176         return git_default_email.buf;
 177 }
 178
 179 static const char *ident_default_date(void)
 180 {
 181         if (!git_default_date.len)
 182                 datestamp(&git_default_date);
 183         return git_default_date.buf;
 184 }
 185
 186 static int crud(unsigned char c)
 187 {
 188         return  c <= 32  ||
 189                 c == '.' ||
 190                 c == ',' ||
 191                 c == ':' ||
 192                 c == ';' ||
 193                 c == '<' ||
 194                 c == '>' ||
 195                 c == '"' ||
 196                 c == '\\' ||
 197                 c == '\'';
 198 }
 199
 200 /*
 201  * Copy over a string to the destination, but avoid special
 202  * characters ('\n', '<' and '>') and remove crud at the end
 203  */
 204 static void strbuf_addstr_without_crud(struct strbuf *sb, const char *src)
 205 {
 206         size_t i, len;
 207         unsigned char c;
 208
 209         /* Remove crud from the beginning.. */
 210         while ((c = *src) != 0) {
 211                 if (!crud(c))
 212                         break;
 213                 src++;
 214         }
 215
 216         /* Remove crud from the end.. */
 217         len = strlen(src);
 218         while (len > 0) {
 219                 c = src[len-1];
 220                 if (!crud(c))
 221                         break;
 222                 --len;
 223         }
 224
 225         /*
 226          * Copy the rest to the buffer, but avoid the special
 227          * characters '\n' '<' and '>' that act as delimiters on
 228          * an identification line. We can only remove crud, never add it,
 229          * so 'len' is our maximum.
 230          */
 231         strbuf_grow(sb, len);
 232         for (i = 0; i < len; i++) {
 233                 c = *src++;
 234                 switch (c) {
 235                 case '\n': case '<': case '>':
 236                         continue;
 237                 }
 238                 sb->buf[sb->len++] = c;
 239         }
 240         sb->buf[sb->len] = '\0';
 241 }
 242
 243 /*
 244  * Reverse of fmt_ident(); given an ident line, split the fields
 245  * to allow the caller to parse it.
 246  * Signal a success by returning 0, but date/tz fields of the result
 247  * can still be NULL if the input line only has the name/email part
 248  * (e.g. reading from a reflog entry).
 249  */
 250 int split_ident_line(struct ident_split *split, const char *line, int len)
 251 {
 252         const char *cp;
 253         size_t span;
 254         int status = -1;
 255
 256         memset(split, 0, sizeof(*split));
 257
 258         split->name_begin = line;
 259         for (cp = line; *cp && cp < line + len; cp++)
 260                 if (*cp == '<') {
 261                         split->mail_begin = cp + 1;
 262                         break;
 263                 }
 264         if (!split->mail_begin)
 265                 return status;
 266
 267         for (cp = split->mail_begin - 2; line <= cp; cp--)
 268                 if (!isspace(*cp)) {
 269                         split->name_end = cp + 1;
 270                         break;
 271                 }
 272         if (!split->name_end) {
 273                 /* no human readable name */
 274                 split->name_end = split->name_begin;
 275         }
 276
 277         for (cp = split->mail_begin; cp < line + len; cp++)
 278                 if (*cp == '>') {
 279                         split->mail_end = cp;
 280                         break;
 281                 }
 282         if (!split->mail_end)
 283                 return status;
 284
 285         /*
 286          * Look from the end-of-line to find the trailing ">" of the mail
 287          * address, even though we should already know it as split->mail_end.
 288          * This can help in cases of broken idents with an extra ">" somewhere
 289          * in the email address.  Note that we are assuming the timestamp will
 290          * never have a ">" in it.
 291          *
 292          * Note that we will always find some ">" before going off the front of
 293          * the string, because will always hit the split->mail_end closing
 294          * bracket.
 295          */
 296         for (cp = line + len - 1; *cp != '>'; cp--)
 297                 ;
 298
 299         for (cp = cp + 1; cp < line + len && isspace(*cp); cp++)
 300                 ;
 301         if (line + len <= cp)
 302                 goto person_only;
 303         split->date_begin = cp;
 304         span = strspn(cp, "0123456789");
 305         if (!span)
 306                 goto person_only;
 307         split->date_end = split->date_begin + span;
 308         for (cp = split->date_end; cp < line + len && isspace(*cp); cp++)
 309                 ;
 310         if (line + len <= cp || (*cp != '+' && *cp != '-'))
 311                 goto person_only;
 312         split->tz_begin = cp;
 313         span = strspn(cp + 1, "0123456789");
 314         if (!span)
 315                 goto person_only;
 316         split->tz_end = split->tz_begin + 1 + span;
 317         return 0;
 318
 319 person_only:
 320         split->date_begin = NULL;
 321         split->date_end = NULL;
 322         split->tz_begin = NULL;
 323         split->tz_end = NULL;
 324         return 0;
 325 }
 326
 327 static const char *env_hint =
 328 "\n"
 329 "*** Please tell me who you are.\n"
 330 "\n"
 331 "Run\n"
 332 "\n"
 333 "  git config --global user.email \"you@example.com\"\n"
 334 "  git config --global user.name \"Your Name\"\n"
 335 "\n"
 336 "to set your account\'s default identity.\n"
 337 "Omit --global to set the identity only in this repository.\n"
 338 "\n";
 339
 340 const char *fmt_ident(const char *name, const char *email,
 341                       const char *date_str, int flag)
 342 {
 343         static struct strbuf ident = STRBUF_INIT;
 344         int strict = (flag & IDENT_STRICT);
 345         int want_date = !(flag & IDENT_NO_DATE);
 346         int want_name = !(flag & IDENT_NO_NAME);
 347
 348         if (want_name && !name)
 349                 name = ident_default_name();
 350         if (!email)
 351                 email = ident_default_email();
 352
 353         if (want_name && !*name) {
 354                 struct passwd *pw;
 355
 356                 if (strict) {
 357                         if (name == git_default_name.buf)
 358                                 fputs(env_hint, stderr);
 359                         die("empty ident name (for <%s>) not allowed", email);
 360                 }
 361                 pw = xgetpwuid_self(NULL);
 362                 name = pw->pw_name;
 363         }
 364
 365         if (want_name && strict &&
 366             name == git_default_name.buf && default_name_is_bogus) {
 367                 fputs(env_hint, stderr);
 368                 die("unable to auto-detect name (got '%s')", name);
 369         }
 370
 371         if (strict && email == git_default_email.buf && default_email_is_bogus) {
 372                 fputs(env_hint, stderr);
 373                 die("unable to auto-detect email address (got '%s')", email);
 374         }
 375
 376         strbuf_reset(&ident);
 377         if (want_name) {
 378                 strbuf_addstr_without_crud(&ident, name);
 379                 strbuf_addstr(&ident, " <");
 380         }
 381         strbuf_addstr_without_crud(&ident, email);
 382         if (want_name)
 383                         strbuf_addch(&ident, '>');
 384         if (want_date) {
 385                 strbuf_addch(&ident, ' ');
 386                 if (date_str && date_str[0]) {
 387                         if (parse_date(date_str, &ident) < 0)
 388                                 die("invalid date format: %s", date_str);
 389                 }
 390                 else
 391                         strbuf_addstr(&ident, ident_default_date());
 392         }
 393
 394         return ident.buf;
 395 }
 396
 397 const char *fmt_name(const char *name, const char *email)
 398 {
 399         return fmt_ident(name, email, NULL, IDENT_STRICT | IDENT_NO_DATE);
 400 }
 401
 402 const char *git_author_info(int flag)
 403 {
 404         if (getenv("GIT_AUTHOR_NAME"))
 405                 author_ident_explicitly_given |= IDENT_NAME_GIVEN;
 406         if (getenv("GIT_AUTHOR_EMAIL"))
 407                 author_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 408         return fmt_ident(getenv("GIT_AUTHOR_NAME"),
 409                          getenv("GIT_AUTHOR_EMAIL"),
 410                          getenv("GIT_AUTHOR_DATE"),
 411                          flag);
 412 }
 413
 414 const char *git_committer_info(int flag)
 415 {
 416         if (getenv("GIT_COMMITTER_NAME"))
 417                 committer_ident_explicitly_given |= IDENT_NAME_GIVEN;
 418         if (getenv("GIT_COMMITTER_EMAIL"))
 419                 committer_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 420         return fmt_ident(getenv("GIT_COMMITTER_NAME"),
 421                          getenv("GIT_COMMITTER_EMAIL"),
 422                          getenv("GIT_COMMITTER_DATE"),
 423                          flag);
 424 }
 425
 426 static int ident_is_sufficient(int user_ident_explicitly_given)
 427 {
 428 #ifndef WINDOWS
 429         return (user_ident_explicitly_given & IDENT_MAIL_GIVEN);
 430 #else
 431         return (user_ident_explicitly_given == IDENT_ALL_GIVEN);
 432 #endif
 433 }
 434
 435 int committer_ident_sufficiently_given(void)
 436 {
 437         return ident_is_sufficient(committer_ident_explicitly_given);
 438 }
 439
 440 int author_ident_sufficiently_given(void)
 441 {
 442         return ident_is_sufficient(author_ident_explicitly_given);
 443 }
 444
 445 int git_ident_config(const char *var, const char *value, void *data)
 446 {
 447         if (!strcmp(var, "user.name")) {
 448                 if (!value)
 449                         return config_error_nonbool(var);
 450                 strbuf_reset(&git_default_name);
 451                 strbuf_addstr(&git_default_name, value);
 452                 committer_ident_explicitly_given |= IDENT_NAME_GIVEN;
 453                 author_ident_explicitly_given |= IDENT_NAME_GIVEN;
 454                 return 0;
 455         }
 456
 457         if (!strcmp(var, "user.email")) {
 458                 if (!value)
 459                         return config_error_nonbool(var);
 460                 strbuf_reset(&git_default_email);
 461                 strbuf_addstr(&git_default_email, value);
 462                 committer_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 463                 author_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 464                 return 0;
 465         }
 466
 467         return 0;
 468 }
 469
 470 static int buf_cmp(const char *a_begin, const char *a_end,
 471                    const char *b_begin, const char *b_end)
 472 {
 473         int a_len = a_end - a_begin;
 474         int b_len = b_end - b_begin;
 475         int min = a_len < b_len ? a_len : b_len;
 476         int cmp;
 477
 478         cmp = memcmp(a_begin, b_begin, min);
 479         if (cmp)
 480                 return cmp;
 481
 482         return a_len - b_len;
 483 }
 484
 485 int ident_cmp(const struct ident_split *a,
 486               const struct ident_split *b)
 487 {
 488         int cmp;
 489
 490         cmp = buf_cmp(a->mail_begin, a->mail_end,
 491                       b->mail_begin, b->mail_end);
 492         if (cmp)
 493                 return cmp;
 494
 495         return buf_cmp(a->name_begin, a->name_end,
 496                        b->name_begin, b->name_end);
 497 }