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 char git_default_date[50];
  11
  12 #ifdef NO_GECOS_IN_PWENT
  13 #define get_gecos(ignored) "&"
  14 #else
  15 #define get_gecos(struct_passwd) ((struct_passwd)->pw_gecos)
  16 #endif
  17
  18 static void copy_gecos(const struct passwd *w, char *name, size_t sz)
  19 {
  20         char *src, *dst;
  21         size_t len, nlen;
  22
  23         nlen = strlen(w->pw_name);
  24
  25         /* Traditionally GECOS field had office phone numbers etc, separated
  26          * with commas.  Also & stands for capitalized form of the login name.
  27          */
  28
  29         for (len = 0, dst = name, src = get_gecos(w); len < sz; src++) {
  30                 int ch = *src;
  31                 if (ch != '&') {
  32                         *dst++ = ch;
  33                         if (ch == 0 || ch == ',')
  34                                 break;
  35                         len++;
  36                         continue;
  37                 }
  38                 if (len + nlen < sz) {
  39                         /* Sorry, Mr. McDonald... */
  40                         *dst++ = toupper(*w->pw_name);
  41                         memcpy(dst, w->pw_name + 1, nlen - 1);
  42                         dst += nlen - 1;
  43                         len += nlen;
  44                 }
  45         }
  46         if (len < sz)
  47                 name[len] = 0;
  48         else
  49                 die("Your parents must have hated you!");
  50
  51 }
  52
  53 static int add_mailname_host(char *buf, size_t len)
  54 {
  55         FILE *mailname;
  56
  57         mailname = fopen("/etc/mailname", "r");
  58         if (!mailname) {
  59                 if (errno != ENOENT)
  60                         warning("cannot open /etc/mailname: %s",
  61                                 strerror(errno));
  62                 return -1;
  63         }
  64         if (!fgets(buf, len, mailname)) {
  65                 if (ferror(mailname))
  66                         warning("cannot read /etc/mailname: %s",
  67                                 strerror(errno));
  68                 fclose(mailname);
  69                 return -1;
  70         }
  71         /* success! */
  72         fclose(mailname);
  73         return 0;
  74 }
  75
  76 static void add_domainname(char *buf, size_t len)
  77 {
  78         struct hostent *he;
  79         size_t namelen;
  80         const char *domainname;
  81
  82         if (gethostname(buf, len)) {
  83                 warning("cannot get host name: %s", strerror(errno));
  84                 strlcpy(buf, "(none)", len);
  85                 return;
  86         }
  87         namelen = strlen(buf);
  88         if (memchr(buf, '.', namelen))
  89                 return;
  90
  91         he = gethostbyname(buf);
  92         buf[namelen++] = '.';
  93         buf += namelen;
  94         len -= namelen;
  95         if (he && (domainname = strchr(he->h_name, '.')))
  96                 strlcpy(buf, domainname + 1, len);
  97         else
  98                 strlcpy(buf, "(none)", len);
  99 }
 100
 101 static void copy_email(const struct passwd *pw)
 102 {
 103         /*
 104          * Make up a fake email address
 105          * (name + '@' + hostname [+ '.' + domainname])
 106          */
 107         size_t len = strlen(pw->pw_name);
 108         if (len > sizeof(git_default_email)/2)
 109                 die("Your sysadmin must hate you!");
 110         memcpy(git_default_email, pw->pw_name, len);
 111         git_default_email[len++] = '@';
 112
 113         if (!add_mailname_host(git_default_email + len,
 114                                 sizeof(git_default_email) - len))
 115                 return; /* read from "/etc/mailname" (Debian) */
 116         add_domainname(git_default_email + len,
 117                         sizeof(git_default_email) - len);
 118 }
 119
 120 static void setup_ident(const char **name, const char **emailp)
 121 {
 122         struct passwd *pw = NULL;
 123
 124         /* Get the name ("gecos") */
 125         if (!*name && !git_default_name[0]) {
 126                 pw = getpwuid(getuid());
 127                 if (!pw)
 128                         die("You don't exist. Go away!");
 129                 copy_gecos(pw, git_default_name, sizeof(git_default_name));
 130         }
 131         if (!*name)
 132                 *name = git_default_name;
 133
 134         if (!*emailp && !git_default_email[0]) {
 135                 const char *email = getenv("EMAIL");
 136
 137                 if (email && email[0]) {
 138                         strlcpy(git_default_email, email,
 139                                 sizeof(git_default_email));
 140                         user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 141                 } else {
 142                         if (!pw)
 143                                 pw = getpwuid(getuid());
 144                         if (!pw)
 145                                 die("You don't exist. Go away!");
 146                         copy_email(pw);
 147                 }
 148         }
 149         if (!*emailp)
 150                 *emailp = git_default_email;
 151
 152         /* And set the default date */
 153         if (!git_default_date[0])
 154                 datestamp(git_default_date, sizeof(git_default_date));
 155 }
 156
 157 static int add_raw(char *buf, size_t size, int offset, const char *str)
 158 {
 159         size_t len = strlen(str);
 160         if (offset + len > size)
 161                 return size;
 162         memcpy(buf + offset, str, len);
 163         return offset + len;
 164 }
 165
 166 static int crud(unsigned char c)
 167 {
 168         return  c <= 32  ||
 169                 c == '.' ||
 170                 c == ',' ||
 171                 c == ':' ||
 172                 c == ';' ||
 173                 c == '<' ||
 174                 c == '>' ||
 175                 c == '"' ||
 176                 c == '\\' ||
 177                 c == '\'';
 178 }
 179
 180 /*
 181  * Copy over a string to the destination, but avoid special
 182  * characters ('\n', '<' and '>') and remove crud at the end
 183  */
 184 static int copy(char *buf, size_t size, int offset, const char *src)
 185 {
 186         size_t i, len;
 187         unsigned char c;
 188
 189         /* Remove crud from the beginning.. */
 190         while ((c = *src) != 0) {
 191                 if (!crud(c))
 192                         break;
 193                 src++;
 194         }
 195
 196         /* Remove crud from the end.. */
 197         len = strlen(src);
 198         while (len > 0) {
 199                 c = src[len-1];
 200                 if (!crud(c))
 201                         break;
 202                 --len;
 203         }
 204
 205         /*
 206          * Copy the rest to the buffer, but avoid the special
 207          * characters '\n' '<' and '>' that act as delimiters on
 208          * an identification line
 209          */
 210         for (i = 0; i < len; i++) {
 211                 c = *src++;
 212                 switch (c) {
 213                 case '\n': case '<': case '>':
 214                         continue;
 215                 }
 216                 if (offset >= size)
 217                         return size;
 218                 buf[offset++] = c;
 219         }
 220         return offset;
 221 }
 222
 223 /*
 224  * Reverse of fmt_ident(); given an ident line, split the fields
 225  * to allow the caller to parse it.
 226  * Signal a success by returning 0, but date/tz fields of the result
 227  * can still be NULL if the input line only has the name/email part
 228  * (e.g. reading from a reflog entry).
 229  */
 230 int split_ident_line(struct ident_split *split, const char *line, int len)
 231 {
 232         const char *cp;
 233         size_t span;
 234         int status = -1;
 235
 236         memset(split, 0, sizeof(*split));
 237
 238         split->name_begin = line;
 239         for (cp = line; *cp && cp < line + len; cp++)
 240                 if (*cp == '<') {
 241                         split->mail_begin = cp + 1;
 242                         break;
 243                 }
 244         if (!split->mail_begin)
 245                 return status;
 246
 247         for (cp = split->mail_begin - 2; line < cp; cp--)
 248                 if (!isspace(*cp)) {
 249                         split->name_end = cp + 1;
 250                         break;
 251                 }
 252         if (!split->name_end)
 253                 return status;
 254
 255         for (cp = split->mail_begin; cp < line + len; cp++)
 256                 if (*cp == '>') {
 257                         split->mail_end = cp;
 258                         break;
 259                 }
 260         if (!split->mail_end)
 261                 return status;
 262
 263         for (cp = split->mail_end + 1; cp < line + len && isspace(*cp); cp++)
 264                 ;
 265         if (line + len <= cp)
 266                 goto person_only;
 267         split->date_begin = cp;
 268         span = strspn(cp, "0123456789");
 269         if (!span)
 270                 goto person_only;
 271         split->date_end = split->date_begin + span;
 272         for (cp = split->date_end; cp < line + len && isspace(*cp); cp++)
 273                 ;
 274         if (line + len <= cp || (*cp != '+' && *cp != '-'))
 275                 goto person_only;
 276         split->tz_begin = cp;
 277         span = strspn(cp + 1, "0123456789");
 278         if (!span)
 279                 goto person_only;
 280         split->tz_end = split->tz_begin + 1 + span;
 281         return 0;
 282
 283 person_only:
 284         split->date_begin = NULL;
 285         split->date_end = NULL;
 286         split->tz_begin = NULL;
 287         split->tz_end = NULL;
 288         return 0;
 289 }
 290
 291 static const char *env_hint =
 292 "\n"
 293 "*** Please tell me who you are.\n"
 294 "\n"
 295 "Run\n"
 296 "\n"
 297 "  git config --global user.email \"you@example.com\"\n"
 298 "  git config --global user.name \"Your Name\"\n"
 299 "\n"
 300 "to set your account\'s default identity.\n"
 301 "Omit --global to set the identity only in this repository.\n"
 302 "\n";
 303
 304 const char *fmt_ident(const char *name, const char *email,
 305                       const char *date_str, int flag)
 306 {
 307         static char buffer[1000];
 308         char date[50];
 309         int i;
 310         int error_on_no_name = (flag & IDENT_ERROR_ON_NO_NAME);
 311         int warn_on_no_name = (flag & IDENT_WARN_ON_NO_NAME);
 312         int name_addr_only = (flag & IDENT_NO_DATE);
 313
 314         setup_ident(&name, &email);
 315
 316         if (!*name) {
 317                 struct passwd *pw;
 318
 319                 if ((warn_on_no_name || error_on_no_name) &&
 320                     name == git_default_name && env_hint) {
 321                         fputs(env_hint, stderr);
 322                         env_hint = NULL; /* warn only once */
 323                 }
 324                 if (error_on_no_name)
 325                         die("empty ident %s <%s> not allowed", name, email);
 326                 pw = getpwuid(getuid());
 327                 if (!pw)
 328                         die("You don't exist. Go away!");
 329                 strlcpy(git_default_name, pw->pw_name,
 330                         sizeof(git_default_name));
 331                 name = git_default_name;
 332         }
 333
 334         strcpy(date, git_default_date);
 335         if (!name_addr_only && date_str && date_str[0]) {
 336                 if (parse_date(date_str, date, sizeof(date)) < 0)
 337                         die("invalid date format: %s", date_str);
 338         }
 339
 340         i = copy(buffer, sizeof(buffer), 0, name);
 341         i = add_raw(buffer, sizeof(buffer), i, " <");
 342         i = copy(buffer, sizeof(buffer), i, email);
 343         if (!name_addr_only) {
 344                 i = add_raw(buffer, sizeof(buffer), i,  "> ");
 345                 i = copy(buffer, sizeof(buffer), i, date);
 346         } else {
 347                 i = add_raw(buffer, sizeof(buffer), i, ">");
 348         }
 349         if (i >= sizeof(buffer))
 350                 die("Impossibly long personal identifier");
 351         buffer[i] = 0;
 352         return buffer;
 353 }
 354
 355 const char *fmt_name(const char *name, const char *email)
 356 {
 357         return fmt_ident(name, email, NULL, IDENT_ERROR_ON_NO_NAME | IDENT_NO_DATE);
 358 }
 359
 360 const char *git_author_info(int flag)
 361 {
 362         return fmt_ident(getenv("GIT_AUTHOR_NAME"),
 363                          getenv("GIT_AUTHOR_EMAIL"),
 364                          getenv("GIT_AUTHOR_DATE"),
 365                          flag);
 366 }
 367
 368 const char *git_committer_info(int flag)
 369 {
 370         if (getenv("GIT_COMMITTER_NAME"))
 371                 user_ident_explicitly_given |= IDENT_NAME_GIVEN;
 372         if (getenv("GIT_COMMITTER_EMAIL"))
 373                 user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 374         return fmt_ident(getenv("GIT_COMMITTER_NAME"),
 375                          getenv("GIT_COMMITTER_EMAIL"),
 376                          getenv("GIT_COMMITTER_DATE"),
 377                          flag);
 378 }
 379
 380 int user_ident_sufficiently_given(void)
 381 {
 382 #ifndef WINDOWS
 383         return (user_ident_explicitly_given & IDENT_MAIL_GIVEN);
 384 #else
 385         return (user_ident_explicitly_given == IDENT_ALL_GIVEN);
 386 #endif
 387 }