git/builtin-mailsplit.c

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4.2 KiB
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/*
* Totally braindamaged mbox splitter program.
*
* It just splits a mbox into a list of files: "0001" "0002" ..
* so you can process them further from there.
*/
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <stdio.h>
#include "cache.h"
#include "builtin.h"
static const char git_mailsplit_usage[] =
"git-mailsplit [-d<prec>] [-f<n>] [-b] -o<directory> <mbox>...";
static int is_from_line(const char *line, int len)
{
const char *colon;
if (len < 20 || memcmp("From ", line, 5))
return 0;
colon = line + len - 2;
line += 5;
for (;;) {
if (colon < line)
return 0;
if (*--colon == ':')
break;
}
if (!isdigit(colon[-4]) ||
!isdigit(colon[-2]) ||
!isdigit(colon[-1]) ||
!isdigit(colon[ 1]) ||
!isdigit(colon[ 2]))
return 0;
/* year */
if (strtol(colon+3, NULL, 10) <= 90)
return 0;
/* Ok, close enough */
return 1;
}
/* Could be as small as 64, enough to hold a Unix "From " line. */
static char buf[4096];
/* Called with the first line (potentially partial)
* already in buf[] -- normally that should begin with
* the Unix "From " line. Write it into the specified
* file.
*/
static int split_one(FILE *mbox, const char *name, int allow_bare)
{
FILE *output = NULL;
int len = strlen(buf);
int fd;
int status = 0;
int is_bare = !is_from_line(buf, len);
if (is_bare && !allow_bare)
goto corrupt;
fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0666);
if (fd < 0)
die("cannot open output file %s", name);
output = fdopen(fd, "w");
/* Copy it out, while searching for a line that begins with
* "From " and having something that looks like a date format.
*/
for (;;) {
int is_partial = (buf[len-1] != '\n');
if (fputs(buf, output) == EOF)
die("cannot write output");
if (fgets(buf, sizeof(buf), mbox) == NULL) {
if (feof(mbox)) {
status = 1;
break;
}
die("cannot read mbox");
}
len = strlen(buf);
if (!is_partial && !is_bare && is_from_line(buf, len))
break; /* done with one message */
}
fclose(output);
return status;
corrupt:
if (output)
fclose(output);
unlink(name);
fprintf(stderr, "corrupt mailbox\n");
exit(1);
}
int split_mbox(const char **mbox, const char *dir, int allow_bare, int nr_prec, int skip)
{
char *name = xmalloc(strlen(dir) + 2 + 3 * sizeof(skip));
int ret = -1;
while (*mbox) {
const char *file = *mbox++;
FILE *f = !strcmp(file, "-") ? stdin : fopen(file, "r");
int file_done = 0;
if ( !f ) {
error("cannot open mbox %s", file);
goto out;
}
if (fgets(buf, sizeof(buf), f) == NULL) {
if (f == stdin)
break; /* empty stdin is OK */
error("cannot read mbox %s", file);
goto out;
}
while (!file_done) {
sprintf(name, "%s/%0*d", dir, nr_prec, ++skip);
file_done = split_one(f, name, allow_bare);
}
if (f != stdin)
fclose(f);
}
ret = skip;
out:
free(name);
return ret;
}
int cmd_mailsplit(int argc, const char **argv, const char *prefix)
{
int nr = 0, nr_prec = 4, ret;
int allow_bare = 0;
const char *dir = NULL;
const char **argp;
static const char *stdin_only[] = { "-", NULL };
for (argp = argv+1; *argp; argp++) {
const char *arg = *argp;
if (arg[0] != '-')
break;
/* do flags here */
if ( arg[1] == 'd' ) {
nr_prec = strtol(arg+2, NULL, 10);
if (nr_prec < 3 || 10 <= nr_prec)
usage(git_mailsplit_usage);
continue;
} else if ( arg[1] == 'f' ) {
nr = strtol(arg+2, NULL, 10);
} else if ( arg[1] == 'b' && !arg[2] ) {
allow_bare = 1;
} else if ( arg[1] == 'o' && arg[2] ) {
dir = arg+2;
} else if ( arg[1] == '-' && !arg[2] ) {
argp++; /* -- marks end of options */
break;
} else {
die("unknown option: %s", arg);
}
}
if ( !dir ) {
/* Backwards compatibility: if no -o specified, accept
<mbox> <dir> or just <dir> */
switch (argc - (argp-argv)) {
case 1:
dir = argp[0];
argp = stdin_only;
break;
case 2:
stdin_only[0] = argp[0];
dir = argp[1];
argp = stdin_only;
break;
default:
usage(git_mailsplit_usage);
}
} else {
/* New usage: if no more argument, parse stdin */
if ( !*argp )
argp = stdin_only;
}
ret = split_mbox(argp, dir, allow_bare, nr_prec, nr);
if (ret != -1)
printf("%d\n", ret);
return ret == -1;
}