Andrew's git - gitweb.git/blob

   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 <sys/mman.h>
  13#include <string.h>
  14#include <stdio.h>
  15#include <ctype.h>
  16#include <assert.h>
  17#include "cache.h"
  18
  19static const char git_mailsplit_usage[] =
  20"git-mailsplit [-d<prec>] [<mbox>] <directory>";
  21
  22static int is_from_line(const char *line, int len)
  23{
  24        const char *colon;
  25
  26        if (len < 20 || memcmp("From ", line, 5))
  27                return 0;
  28
  29        colon = line + len - 2;
  30        line += 5;
  31        for (;;) {
  32                if (colon < line)
  33                        return 0;
  34                if (*--colon == ':')
  35                        break;
  36        }
  37
  38        if (!isdigit(colon[-4]) ||
  39            !isdigit(colon[-2]) ||
  40            !isdigit(colon[-1]) ||
  41            !isdigit(colon[ 1]) ||
  42            !isdigit(colon[ 2]))
  43                return 0;
  44
  45        /* year */
  46        if (strtol(colon+3, NULL, 10) <= 90)
  47                return 0;
  48
  49        /* Ok, close enough */
  50        return 1;
  51}
  52
  53/* Could be as small as 64, enough to hold a Unix "From " line. */
  54static char buf[4096];
  55
  56/* Called with the first line (potentially partial)
  57 * already in buf[] -- normally that should begin with
  58 * the Unix "From " line.  Write it into the specified
  59 * file.
  60 */
  61static int split_one(FILE *mbox, const char *name)
  62{
  63        FILE *output = NULL;
  64        int len = strlen(buf);
  65        int fd;
  66        int status = 0;
  67
  68        if (!is_from_line(buf, len))
  69                goto corrupt;
  70
  71        fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0666);
  72        if (fd < 0)
  73                die("cannot open output file %s", name);
  74        output = fdopen(fd, "w");
  75
  76        /* Copy it out, while searching for a line that begins with
  77         * "From " and having something that looks like a date format.
  78         */
  79        for (;;) {
  80                int is_partial = (buf[len-1] != '\n');
  81
  82                if (fputs(buf, output) == EOF)
  83                        die("cannot write output");
  84
  85                if (fgets(buf, sizeof(buf), mbox) == NULL) {
  86                        if (feof(mbox)) {
  87                                status = 1;
  88                                break;
  89                        }
  90                        die("cannot read mbox");
  91                }
  92                len = strlen(buf);
  93                if (!is_partial && is_from_line(buf, len))
  94                        break; /* done with one message */
  95        }
  96        fclose(output);
  97        return status;
  98
  99 corrupt:
 100        if (output)
 101                fclose(output);
 102        unlink(name);
 103        fprintf(stderr, "corrupt mailbox\n");
 104        exit(1);
 105}
 106
 107int main(int argc, const char **argv)
 108{
 109        int i, nr, nr_prec = 4;
 110        FILE *mbox = NULL;
 111
 112        for (i = 1; i < argc; i++) {
 113                const char *arg = argv[i];
 114
 115                if (arg[0] != '-')
 116                        break;
 117                /* do flags here */
 118                if (!strncmp(arg, "-d", 2)) {
 119                        nr_prec = strtol(arg + 2, NULL, 10);
 120                        if (nr_prec < 3 || 10 <= nr_prec)
 121                                usage(git_mailsplit_usage);
 122                        continue;
 123                }
 124        }
 125
 126        /* Either one remaining arg (dir), or two (mbox and dir) */
 127        switch (argc - i) {
 128        case 1:
 129                mbox = stdin;
 130                break;
 131        case 2:
 132                if ((mbox = fopen(argv[i], "r")) == NULL)
 133                        die("cannot open mbox %s for reading", argv[i]);
 134                break;
 135        default:
 136                usage(git_mailsplit_usage);
 137        }
 138        if (chdir(argv[argc - 1]) < 0)
 139                usage(git_mailsplit_usage);
 140
 141        nr = 0;
 142        if (fgets(buf, sizeof(buf), mbox) == NULL)
 143                die("cannot read mbox");
 144
 145        for (;;) {
 146                char name[10];
 147
 148                sprintf(name, "%0*d", nr_prec, ++nr);
 149                switch (split_one(mbox, name)) {
 150                case 0:
 151                        break;
 152                case 1:
 153                        printf("%d\n", nr);
 154                        return 0;
 155                default:
 156                        exit(1);
 157                }
 158        }
 159}