mailsplit.con commit Bugfix: stop if directory already exists (b0c698a)
   1/*
   2 * Totally braindamaged mbox splitter program.
   3 *
   4 * It just splits a mbox into a list of files: "0001" "0002" ..
   5 * so you can process them further from there.
   6 */
   7#include <unistd.h>
   8#include <stdlib.h>
   9#include <fcntl.h>
  10#include <sys/types.h>
  11#include <sys/stat.h>
  12#include <string.h>
  13#include <stdio.h>
  14#include <assert.h>
  15#include "cache.h"
  16
  17static const char git_mailsplit_usage[] =
  18"git-mailsplit [-d<prec>] [<mbox>] <directory>";
  19
  20static int is_from_line(const char *line, int len)
  21{
  22        const char *colon;
  23
  24        if (len < 20 || memcmp("From ", line, 5))
  25                return 0;
  26
  27        colon = line + len - 2;
  28        line += 5;
  29        for (;;) {
  30                if (colon < line)
  31                        return 0;
  32                if (*--colon == ':')
  33                        break;
  34        }
  35
  36        if (!isdigit(colon[-4]) ||
  37            !isdigit(colon[-2]) ||
  38            !isdigit(colon[-1]) ||
  39            !isdigit(colon[ 1]) ||
  40            !isdigit(colon[ 2]))
  41                return 0;
  42
  43        /* year */
  44        if (strtol(colon+3, NULL, 10) <= 90)
  45                return 0;
  46
  47        /* Ok, close enough */
  48        return 1;
  49}
  50
  51/* Could be as small as 64, enough to hold a Unix "From " line. */
  52static char buf[4096];
  53
  54/* Called with the first line (potentially partial)
  55 * already in buf[] -- normally that should begin with
  56 * the Unix "From " line.  Write it into the specified
  57 * file.
  58 */
  59static int split_one(FILE *mbox, const char *name)
  60{
  61        FILE *output = NULL;
  62        int len = strlen(buf);
  63        int fd;
  64        int status = 0;
  65
  66        if (!is_from_line(buf, len))
  67                goto corrupt;
  68
  69        fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0666);
  70        if (fd < 0)
  71                die("cannot open output file %s", name);
  72        output = fdopen(fd, "w");
  73
  74        /* Copy it out, while searching for a line that begins with
  75         * "From " and having something that looks like a date format.
  76         */
  77        for (;;) {
  78                int is_partial = (buf[len-1] != '\n');
  79
  80                if (fputs(buf, output) == EOF)
  81                        die("cannot write output");
  82
  83                if (fgets(buf, sizeof(buf), mbox) == NULL) {
  84                        if (feof(mbox)) {
  85                                status = 1;
  86                                break;
  87                        }
  88                        die("cannot read mbox");
  89                }
  90                len = strlen(buf);
  91                if (!is_partial && is_from_line(buf, len))
  92                        break; /* done with one message */
  93        }
  94        fclose(output);
  95        return status;
  96
  97 corrupt:
  98        if (output)
  99                fclose(output);
 100        unlink(name);
 101        fprintf(stderr, "corrupt mailbox\n");
 102        exit(1);
 103}
 104
 105int main(int argc, const char **argv)
 106{
 107        int i, nr, nr_prec = 4;
 108        FILE *mbox = NULL;
 109
 110        for (i = 1; i < argc; i++) {
 111                const char *arg = argv[i];
 112
 113                if (arg[0] != '-')
 114                        break;
 115                /* do flags here */
 116                if (!strncmp(arg, "-d", 2)) {
 117                        nr_prec = strtol(arg + 2, NULL, 10);
 118                        if (nr_prec < 3 || 10 <= nr_prec)
 119                                usage(git_mailsplit_usage);
 120                        continue;
 121                }
 122        }
 123
 124        /* Either one remaining arg (dir), or two (mbox and dir) */
 125        switch (argc - i) {
 126        case 1:
 127                mbox = stdin;
 128                break;
 129        case 2:
 130                if ((mbox = fopen(argv[i], "r")) == NULL)
 131                        die("cannot open mbox %s for reading", argv[i]);
 132                break;
 133        default:
 134                usage(git_mailsplit_usage);
 135        }
 136        if (chdir(argv[argc - 1]) < 0)
 137                usage(git_mailsplit_usage);
 138
 139        nr = 0;
 140        if (fgets(buf, sizeof(buf), mbox) == NULL)
 141                die("cannot read mbox");
 142
 143        for (;;) {
 144                char name[10];
 145
 146                sprintf(name, "%0*d", nr_prec, ++nr);
 147                switch (split_one(mbox, name)) {
 148                case 0:
 149                        break;
 150                case 1:
 151                        printf("%d\n", nr);
 152                        return 0;
 153                default:
 154                        exit(1);
 155                }
 156        }
 157}