mbox-helper/mbox-helper.c

   1 /** Read an mbox
   2  */
   3
   4 #define _GNU_SOURCE
   5 #include <unistd.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <ctype.h>
  10 #include <locale.h>
  11 #include <stdbool.h>
  12 #include <getopt.h>
  13
  14 /** Macros
  15  */
  16 #define LTRIM(pos)              while (isspace(*pos)) { pos++; }
  17 #define STRTOLOWER(str, ptr)    for (ptr = str ; *ptr ; ptr++) { *ptr = tolower(*ptr); }
  18
  19 /** MBox pointer
  20  */
  21 typedef struct
  22 {
  23     FILE *fp; // File pointer
  24     long int lastLine;          // Offset of the precedent line (-1 if invalid)
  25     long int currentLine;       // Offset of the current line
  26     long int messageId;         // Current message Id
  27     long int messageBeginning;  // Offset of the beginning of the message (FROM_ line)
  28
  29     char *line;                 // Line buffer
  30     bool isFrom_;               // Is the current line a From_ line ?
  31 }
  32 MBox;
  33
  34 /** Open a mbox
  35  */
  36 static MBox *openMBox(char *filename)
  37 {
  38     FILE *fp;
  39     MBox *mbox;
  40
  41     fp = fopen(filename, "r");
  42     if (!fp) {
  43         return NULL;
  44     }
  45
  46     mbox = (MBox*)malloc(sizeof(MBox));
  47     mbox->fp               = fp;
  48     mbox->lastLine         = -1;
  49     mbox->currentLine      = 0;
  50     mbox->messageId        = 0;
  51     mbox->messageBeginning = 0;
  52     mbox->line             = NULL;
  53     mbox->isFrom_          = false;
  54     return mbox;
  55 }
  56
  57 /** Close a mbox
  58  */
  59 static void closeMBox(MBox *mbox)
  60 {
  61     if (!mbox) {
  62         return;
  63     }
  64     fclose(mbox->fp);
  65     if (mbox->line) {
  66         free(mbox->line);
  67     }
  68     free(mbox);
  69 }
  70
  71 /** Read a line in a file
  72  */
  73 static char *readLine(MBox *mbox)
  74 {
  75     int length;
  76     mbox->lastLine    = mbox->currentLine;
  77     mbox->currentLine = ftell(mbox->fp);
  78     mbox->isFrom_ = false;
  79
  80     if (!mbox->line) {
  81         mbox->line = (char*)malloc(1001);
  82     }
  83     if (!fgets(mbox->line, 1000, mbox->fp)) {
  84         mbox->currentLine = -1;
  85         return NULL;
  86     }
  87     length = ftell(mbox->fp) - mbox->currentLine;
  88     if (length > 1000) {
  89         length = 1000;
  90     }
  91     if (length) {
  92         while (length >= 0 && (isspace(mbox->line[length]) || mbox->line[length] == '\0')) {
  93             length--;
  94         }
  95         mbox->line[length + 1] = '\0';
  96     }
  97     mbox->isFrom_     = (strstr(mbox->line, "From ") == mbox->line);
  98     if (mbox->isFrom_ && mbox->messageBeginning != mbox->currentLine) {
  99         mbox->messageBeginning = mbox->currentLine;
 100         mbox->messageId++;
 101     }
 102     return mbox->line;
 103 }
 104
 105 #if 0 /* unused right now */
 106 /** Return to the last line
 107  */
 108 static bool lastLine(MBox *mbox)
 109 {
 110     if (mbox->lastLine != -1) {
 111         fseek(mbox->fp, mbox->lastLine, SEEK_SET);
 112         mbox->lastLine = -1;
 113         readLine(mbox);
 114         return true;
 115     }
 116     return false;
 117 }
 118 #endif
 119
 120 static bool readFrom_(MBox *mbox)
 121 {
 122     if (!mbox->isFrom_) {
 123         readLine(mbox);
 124     }
 125     return !!mbox->isFrom_;
 126 }
 127
 128 /** Read a message
 129  */
 130 static void readMessage(MBox *mbox, bool display)
 131 {
 132     if (!readFrom_(mbox)) {
 133         return;
 134     }
 135     while (readLine(mbox)) {
 136         if (mbox->isFrom_) {
 137             return;
 138         }
 139         if (display) {
 140             if (strstr(mbox->line, ">From ") == mbox->line) {
 141                 puts(mbox->line + 1);
 142             } else {
 143                 puts(mbox->line);
 144             }
 145         }
 146     }
 147 }
 148
 149 /** Read the headers of a message
 150  */
 151 static void readHeaders(MBox *mbox, char **headers, int hdrsize)
 152 {
 153     char *current = NULL;
 154     char *pos, *ptr;
 155     int size, i;
 156
 157     if (!readFrom_(mbox)) {
 158         return;
 159     }
 160     printf("%d\n%d\n", (int)mbox->messageId, (int)mbox->messageBeginning);
 161     while (readLine(mbox)) {
 162         if (mbox->isFrom_ || !strlen(mbox->line)) {
 163             break;
 164         }
 165         if (current && strlen(mbox->line) && isspace(*(mbox->line))) {
 166             pos = mbox->line;
 167             LTRIM(pos);
 168             printf(" %s", pos);
 169         } else {
 170             if (current) {
 171                 printf("\n");
 172                 free(current);
 173                 current = NULL;
 174             }
 175             pos = strchr(mbox->line, ':');
 176             if (!pos || pos == mbox->line) {
 177                 continue;
 178             }
 179             size = pos - mbox->line;
 180             for (i = 0 ; i < hdrsize ; i++) {
 181                 if ((int)strlen(headers[i]) == size && strcasestr(mbox->line, headers[i]) == mbox->line) {
 182                     current = (char*)malloc(size + 1);
 183                     strcpy(current, headers[i]);
 184                     current[size] = '\0';
 185                 }
 186             }
 187             if (!current && !hdrsize) {
 188                 current = (char*)malloc(size + 1);
 189                 strncpy(current, mbox->line, size);
 190                 current[size] = '\0';
 191                 STRTOLOWER(current, ptr);
 192             }
 193             if (current) {
 194                 puts(current);
 195                 pos++;
 196                 LTRIM(pos);
 197                 printf("%s", pos);
 198             }
 199         }
 200     }
 201     if (current) {
 202         printf("\n");
 203         free(current);
 204         current = NULL;
 205     }
 206     printf("\n");
 207 }
 208
 209 /** Go back to the beginning of the file
 210  */
 211 static void rewindMBox(MBox *mbox)
 212 {
 213     fseek(mbox->fp, 0, SEEK_SET);
 214     mbox->messageId = 0;
 215     mbox->messageBeginning = 0;
 216     readLine(mbox);
 217 }
 218
 219 /** Go back to the beginning of the message
 220  */
 221 static bool rewindMessage(MBox *mbox)
 222 {
 223     if (mbox->isFrom_) {
 224         return true;
 225     }
 226     fseek(mbox->fp, mbox->messageBeginning, SEEK_SET);
 227     mbox->currentLine = -1;
 228     mbox->lastLine = -1;
 229     readLine(mbox);
 230     return mbox->isFrom_;
 231 }
 232
 233 /** Move to the given offset
 234  */
 235 static bool goToOffset(MBox *mbox, int offset, int idx)
 236 {
 237     fseek(mbox->fp, offset, SEEK_SET);
 238     mbox->currentLine = -1;
 239     mbox->lastLine    = -1;
 240     mbox->messageBeginning = offset;
 241     mbox->messageId   = idx;
 242     readLine(mbox);
 243     if (!mbox->isFrom_) {
 244         return false;
 245     }
 246     return true;
 247 }
 248
 249 /** Move to the given message number
 250  */
 251 static bool goToMessage(MBox *mbox, int idx)
 252 {
 253     if (mbox->messageId > idx) {
 254         rewindMBox(mbox);
 255     } else if(mbox->messageId == idx) {
 256         rewindMessage(mbox);
 257         return true;
 258     } else if (!mbox->isFrom_) {
 259         while (!feof(mbox->fp) && !mbox->isFrom_) {
 260             readLine(mbox);
 261         }
 262         if (feof(mbox->fp)) {
 263             return false;
 264         }
 265     }
 266     while (mbox->messageId < idx && !feof(mbox->fp)) {
 267         readMessage(mbox, false);
 268     }
 269     if (mbox->messageId == idx) {
 270         return true;
 271     }
 272     return false;
 273 }
 274
 275
 276 /** Display the program help
 277  */
 278 static void help(void)
 279 {
 280     printf("Usage: mbox-helper [action] [options] -f filename [header1 [header2 ...]]\n"
 281            "Actions: only the last action given is applied\n"
 282            "    -c               compute the number of messages. If -p is given, process the file starting à the given offset\n"
 283            "    -d               return the headers of the messages given with the -m option. If no header is given in the\n"
 284            "                     command line options, all the headers are returned. The headers are return with the format:\n"
 285            "                        MSG1_ID\\n\n"
 286            "                        MSG1_OFFSET\\n\n"
 287            "                        MSG1_HEADER1_NAME\\n\n"
 288            "                        MSG1_HEADER1_VALUE\\n\n"
 289            "                        MSG1_HEADER2_NAME\\n\n"
 290            "                        MSG2_HEADER2_VALUE\\n\n"
 291            "                        ...\n"
 292            "                     Messages are separated by a blank line\n"
 293            "    -b               return the body of the message given by -m (only 1 message is returned)\n"
 294            "Options:\n"
 295            "    -m begin[:end]   id or range of messages to process\n"
 296            "    -p id:pos        indicate that message `id` begins at offset `pos`\n"
 297            "    -h               print this help\n");
 298 }
 299
 300 /** Display an error message
 301  * This function display the giver error, then show the program help and exit the program
 302  */
 303 static void error(const char *message)
 304 {
 305     fprintf(stderr, "Invalid parameters: %s\n", message);
 306     help();
 307     exit(1);
 308 }
 309
 310 /** Main function
 311  */
 312 int main(int argc, char *argv[])
 313 {
 314     int c, i = 0;
 315     int fmid = -1, lmid = -1;
 316     int pmid = 0, pos = 0;
 317     char *filename = NULL;
 318     char **headers = NULL;
 319     char action = 0;
 320     int headerNb   = 0;
 321     char *endptr;
 322     MBox *mbox;
 323
 324     while ((c = getopt(argc, argv, ":bcdp:hm:f:")) != -1) {
 325         switch (c) {
 326           case 'f':
 327             filename = optarg;
 328             break;
 329           case 'm':
 330             fmid = strtol(optarg, &endptr, 10);
 331             if (endptr == optarg) {
 332                 error("invalid message id");
 333             }
 334             if (*endptr != ':' || !*(endptr+1)) {
 335                 lmid = fmid;
 336             } else {
 337                 lmid = atoi(endptr + 1);
 338             }
 339             break;
 340           case 'p':
 341             if ((endptr = strchr(optarg, ':')) != NULL) {
 342                 pmid = strtol(optarg, &endptr, 10);
 343                 if (*endptr != ':' || !*(endptr+1)) {
 344                    error("invalid position couple given");
 345                 }
 346                 pos = atoi(endptr + 1);
 347             } else {
 348                 error("invalid position given");
 349             }
 350             break;
 351           case 'c': case 'd': case 'b':
 352             action = c;
 353             break;
 354           case 'h':
 355             help();
 356             return 0;
 357           case ':':
 358             fprintf(stderr, "Missing argument to -%c\n", optopt);
 359             break;
 360           case '?':
 361             fprintf(stderr, "Unrecognized option: -%c\n", optopt);
 362             break;
 363         }
 364     }
 365
 366     if (!filename) {
 367         error("no file defined");
 368     }
 369
 370     setlocale(LC_ALL, "C");
 371
 372     headerNb = argc - optind;
 373     headers  = (argv + optind);
 374     for (i = 0 ; i < headerNb ; i++) {
 375         STRTOLOWER(headers[i], endptr);
 376     }
 377
 378     mbox = openMBox(filename);
 379     if (!mbox) {
 380         fprintf(stderr, "can't open file '%s'", filename);
 381         return 1;
 382     }
 383     if ((fmid >= pmid || fmid == -1) && pos) {
 384         if (!goToOffset(mbox, pos, pmid)) {
 385             fprintf(stderr, "Offset %d do not match with a message beginning\n", pos);
 386             rewindMBox(mbox);
 387         }
 388     }
 389     switch (action) {
 390       case 'b':
 391         if (fmid == -1) {
 392             fprintf(stderr, "you have to define a message number");
 393             break;
 394         }
 395         goToMessage(mbox, fmid);
 396         readMessage(mbox, true);
 397         break;
 398       case 'c':
 399         while (!feof(mbox->fp)) {
 400             readLine(mbox);
 401         }
 402         printf("%d\n", (int)(mbox->messageId + 1));
 403         break;
 404       case 'd':
 405         if (fmid == -1) {
 406              fprintf(stderr, "you have to define a message number");
 407              break;
 408         }
 409         for (i = fmid ; i <= lmid ; i++) {
 410             goToMessage(mbox, i);
 411             readHeaders(mbox, headers, headerNb);
 412         }
 413         break;
 414     }
 415     closeMBox(mbox);
 416
 417     return 0;
 418 }