svlogd: do not overrun read buffer (fixes bug 439)

function                                             old     new   delta
rotate                                               513     534     +21
logdirs_reopen                                      1291    1296      +5
processorstart                                       409     385     -24

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2009-07-03 18:31:23 +02:00
parent 97ef65483a
commit c5d07fba29

View File

@ -223,7 +223,6 @@ static void processorstart(struct logdir *ld)
while ((pid = vfork()) == -1)
pause2cannot("vfork for processor", ld->name);
if (!pid) {
char *prog[4];
int fd;
/* child */
@ -256,11 +255,7 @@ static void processorstart(struct logdir *ld)
xmove_fd(fd, 5);
// getenv("SHELL")?
prog[0] = (char*)"sh";
prog[1] = (char*)"-c";
prog[2] = ld->processor;
prog[3] = NULL;
execv("/bin/sh", prog);
execl("/bin/sh", "/bin/sh" + 5, "-c", ld->processor, (char*) NULL);
bb_perror_msg_and_die(FATAL"can't %s processor %s", "run", ld->name);
}
ld->fnsave[26] = sv_ch; /* ...restore */
@ -398,13 +393,14 @@ static unsigned rotate(struct logdir *ld)
pause2cannot("rename current", ld->name);
while ((ld->fdcur = open("current", O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600)) == -1)
pause2cannot("create new current", ld->name);
/* we presume this cannot fail */
ld->filecur = fdopen(ld->fdcur, "a"); ////
while ((ld->filecur = fdopen(ld->fdcur, "a")) == NULL) ////
pause2cannot("create new current", ld->name); /* very unlikely */
setvbuf(ld->filecur, NULL, _IOFBF, linelen); ////
close_on_exec_on(ld->fdcur);
ld->size = 0;
while (fchmod(ld->fdcur, 0644) == -1)
pause2cannot("set mode of current", ld->name);
rmoldest(ld);
processorstart(ld);
}
@ -551,10 +547,11 @@ static unsigned logdir_open(struct logdir *ld, const char *fn)
free(ld->processor); ld->processor = NULL;
/* read config */
i = open_read_close("config", buf, sizeof(buf));
i = open_read_close("config", buf, sizeof(buf) - 1);
if (i < 0 && errno != ENOENT)
bb_perror_msg(WARNING"%s/config", ld->name);
if (i > 0) {
buf[i] = '\0';
if (verbose)
bb_error_msg(INFO"read: %s/config", ld->name);
s = buf;