src/signature.c

   1 /*
   2  * This file is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2,
   4  * as published by the Free Software Foundation.
   5  *
   6  * In addition to the permissions in the GNU General Public License,
   7  * the authors give you unlimited permission to link the compiled
   8  * version of this file into combinations with other programs,
   9  * and to distribute those combinations without any restriction
  10  * coming from the use of this file.  (The General Public License
  11  * restrictions do apply in other respects; for example, they cover
  12  * modification of the file, and distribution when not linked into
  13  * a combined executable.)
  14  *
  15  * This file is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; see the file COPYING.  If not, write to
  22  * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  23  * Boston, MA 02110-1301, USA.
  24  */
  25
  26 #include "common.h"
  27 #include "signature.h"
  28 #include "repository.h"
  29 #include "git2/common.h"
  30
  31 void git_signature_free(git_signature *sig)
  32 {
  33         if (sig == NULL)
  34                 return;
  35
  36         free(sig->name);
  37         free(sig->email);
  38         free(sig);
  39 }
  40
  41 git_signature *git_signature_new(const char *name, const char *email, git_time_t time, int offset)
  42 {
  43         git_signature *p = NULL;
  44
  45         if ((p = git__malloc(sizeof(git_signature))) == NULL)
  46                 goto cleanup;
  47
  48         p->name = git__strdup(name);
  49         p->email = git__strdup(email);
  50         p->when.time = time;
  51         p->when.offset = offset;
  52
  53         if (p->name == NULL || p->email == NULL)
  54                 goto cleanup;
  55
  56         return p;
  57
  58 cleanup:
  59         git_signature_free(p);
  60         return NULL;
  61 }
  62
  63 git_signature *git_signature_dup(const git_signature *sig)
  64 {
  65         return git_signature_new(sig->name, sig->email, sig->when.time, sig->when.offset);
  66 }
  67
  68 git_signature *git_signature_now(const char *name, const char *email)
  69 {
  70         time_t now;
  71         time_t offset;
  72         struct tm *utc_tm, *local_tm;
  73
  74 #ifndef GIT_WIN32
  75         struct tm _utc, _local;
  76 #endif
  77
  78         time(&now);
  79
  80         /**
  81          * On Win32, `gmtime_r` doesn't exist but
  82          * `gmtime` is threadsafe, so we can use that
  83          */
  84 #ifdef GIT_WIN32
  85         utc_tm = gmtime(&now);
  86         local_tm = localtime(&now);
  87 #else
  88         utc_tm = gmtime_r(&now, &_utc);
  89         local_tm = localtime_r(&now, &_local);
  90 #endif
  91
  92         offset = mktime(local_tm) - mktime(utc_tm);
  93         offset /= 60;
  94
  95         /* mktime takes care of setting tm_isdst correctly */
  96         if (local_tm->tm_isdst)
  97                 offset += 60;
  98
  99         return git_signature_new(name, email, now, (int)offset);
 100 }
 101
 102 static int parse_timezone_offset(const char *buffer, long *offset_out)
 103 {
 104         long offset, dec_offset;
 105         int mins, hours;
 106
 107         const char *offset_start;
 108         const char *offset_end;
 109
 110         offset_start = buffer + 1;
 111
 112         if (*offset_start == '\n') {
 113                 *offset_out = 0;
 114                 return GIT_SUCCESS;
 115         }
 116
 117         if (offset_start[0] != '-' && offset_start[0] != '+')
 118                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse TZ offset. It doesn't start with '+' or '-'");
 119
 120         if (git__strtol32(&dec_offset, offset_start + 1, &offset_end, 10) < GIT_SUCCESS)
 121                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse TZ offset. It isn't a number");
 122
 123         if (offset_end - offset_start != 5)
 124                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse TZ offset. Invalid length");
 125
 126         hours = dec_offset / 100;
 127         mins = dec_offset % 100;
 128
 129         if (hours > 14) // see http://www.worldtimezone.com/faq.html
 130                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse TZ offset. Hour value too large");;
 131
 132         if (mins > 59)
 133                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse TZ offset. Minute value too large");
 134
 135         offset = (hours * 60) + mins;
 136
 137         if (offset_start[0] == '-')
 138                 offset *= -1;
 139
 140         *offset_out = offset;
 141
 142         return GIT_SUCCESS;
 143 }
 144
 145
 146 int git_signature__parse(git_signature *sig, const char **buffer_out,
 147                 const char *buffer_end, const char *header)
 148 {
 149         const size_t header_len = strlen(header);
 150
 151         int name_length, email_length;
 152         const char *buffer = *buffer_out;
 153         const char *line_end, *name_end, *email_end;
 154         long offset = 0, time;
 155
 156         memset(sig, 0x0, sizeof(git_signature));
 157
 158         line_end = memchr(buffer, '\n', buffer_end - buffer);
 159         if (!line_end)
 160                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. No newline found");;
 161
 162         if (buffer + (header_len + 1) > line_end)
 163                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Signature too short");
 164
 165         if (memcmp(buffer, header, header_len) != 0)
 166                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Expected prefix '%s' doesn't match actual", header);
 167
 168         buffer += header_len;
 169
 170         /* Parse name */
 171         if ((name_end = memchr(buffer, '<', buffer_end - buffer)) == NULL)
 172                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Can't find e-mail start");
 173
 174         name_length = name_end - buffer - 1;
 175         sig->name = git__malloc(name_length + 1);
 176         if (sig->name == NULL)
 177                 return GIT_ENOMEM;
 178
 179         memcpy(sig->name, buffer, name_length);
 180         sig->name[name_length] = 0;
 181         buffer = name_end + 1;
 182
 183         if (buffer >= line_end)
 184                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Ended unexpectedly");
 185
 186         /* Parse email */
 187         if ((email_end = memchr(buffer, '>', buffer_end - buffer)) == NULL)
 188                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Can't find e-mail end");
 189
 190         email_length = email_end - buffer;
 191         sig->email = git__malloc(email_length + 1);
 192         if (sig->name == NULL)
 193                 return GIT_ENOMEM;
 194
 195         memcpy(sig->email, buffer, email_length);
 196         sig->email[email_length] = 0;
 197         buffer = email_end + 1;
 198
 199         if (buffer >= line_end)
 200                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Ended unexpectedly");
 201
 202         if (git__strtol32(&time, buffer, &buffer, 10) < GIT_SUCCESS)
 203                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Timestamp isn't a number");
 204
 205         sig->when.time = (time_t)time;
 206
 207         if (parse_timezone_offset(buffer, &offset) < GIT_SUCCESS)
 208                 return git__throw(GIT_EOBJCORRUPTED, "Failed to parse signature. Could not parse timezone offset");
 209
 210         sig->when.offset = offset;
 211
 212         *buffer_out = (line_end + 1);
 213         return GIT_SUCCESS;
 214 }
 215
 216 int git_signature__write(char **signature, const char *header, const git_signature *sig)
 217 {
 218         int offset, hours, mins;
 219         char sig_buffer[2048];
 220         int sig_buffer_len;
 221         char sign;
 222
 223         offset = sig->when.offset;
 224         sign = (sig->when.offset < 0) ? '-' : '+';
 225
 226         if (offset < 0)
 227                 offset = -offset;
 228
 229         hours = offset / 60;
 230         mins = offset % 60;
 231
 232         sig_buffer_len = snprintf(sig_buffer, sizeof(sig_buffer),
 233                         "%s %s <%s> %u %c%02d%02d\n",
 234                         header, sig->name, sig->email,
 235                         (unsigned)sig->when.time, sign, hours, mins);
 236
 237         if (sig_buffer_len < 0 || (size_t)sig_buffer_len > sizeof(sig_buffer))
 238                 return GIT_ENOMEM;
 239
 240         *signature = git__strdup(sig_buffer);
 241         return sig_buffer_len;
 242 }
 243
 244