[systemd-devel] [PATCH] journal: get rid of LINE_MAX in sd_journal_printv*()
harald at redhat.com
harald at redhat.com
Mon Apr 15 07:12:51 PDT 2013
From: Harald Hoyer <harald at redhat.com>
use stack_size_guess() to get rid of LINE_MAX
---
src/journal/journal-send.c | 99 +++++++++++++++++++++++++++++++----------
src/journal/test-journal-send.c | 92 +++++++++++++++++++++++++++++++++-----
2 files changed, 156 insertions(+), 35 deletions(-)
diff --git a/src/journal/journal-send.c b/src/journal/journal-send.c
index 4b9109a..2ff04b4 100644
--- a/src/journal/journal-send.c
+++ b/src/journal/journal-send.c
@@ -26,6 +26,7 @@
#include <unistd.h>
#include <fcntl.h>
#include <printf.h>
+#include <sys/resource.h>
#define SD_JOURNAL_SUPPRESS_LOCATION
@@ -35,15 +36,17 @@
#define SNDBUF_SIZE (8*1024*1024)
-#define ALLOCA_CODE_FUNC(f, func) \
- do { \
- size_t _fl; \
- const char *_func = (func); \
- char **_f = &(f); \
- _fl = strlen(_func) + 1; \
- *_f = alloca(_fl + 10); \
- memcpy(*_f, "CODE_FUNC=", 10); \
- memcpy(*_f + 10, _func, _fl); \
+#define ALLOCA_CODE_FUNC(f, func) \
+ do { \
+ size_t _fl; \
+ const char *_func = (func); \
+ char **_f = &(f); \
+ _fl = strlen(_func) + 1; \
+ if (stack_size_guess() < (_fl + 10)) \
+ return -ENOMEM; \
+ *_f = alloca(_fl + 10); \
+ memcpy(*_f, "CODE_FUNC=", 10); \
+ memcpy(*_f + 10, _func, _fl); \
} while(false)
/* We open a single fd, and we'll share it with the current process,
@@ -85,11 +88,9 @@ _public_ int sd_journal_print(int priority, const char *format, ...) {
}
_public_ int sd_journal_printv(int priority, const char *format, va_list ap) {
-
- /* FIXME: Instead of limiting things to LINE_MAX we could do a
- C99 variable-length array on the stack here in a loop. */
-
- char buffer[8 + LINE_MAX], p[11]; struct iovec iov[2];
+ char p[11], *buffer; struct iovec iov[2];
+ int len = 0;
+ rlim_t sts = RLIM_INFINITY;
if (priority < 0 || priority > 7)
return -EINVAL;
@@ -97,12 +98,37 @@ _public_ int sd_journal_printv(int priority, const char *format, va_list ap) {
if (!format)
return -EINVAL;
- snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK);
- char_array_0(p);
+ {
+ va_list aq;
+ va_copy(aq, ap);
+ len = vsnprintf(NULL, 0, format, aq);
+ va_end(aq);
+ }
+ if (len <= 0)
+ return -EINVAL;
+
+ sts = stack_size_guess();
+
+ /* Limit the maximum size to the send buffer minus some
+ bytes for the rest
+ */
+ if (sts == RLIM_INFINITY)
+ sts = SNDBUF_SIZE - 1024;
+
+ /* Spare at least one page_size of stack */
+ if (sts < (unsigned)(len + page_size()))
+ len = sts - page_size();
+
+ if (len < 0)
+ return -ENOMEM;
+
+ buffer = alloca(len + 9);
memcpy(buffer, "MESSAGE=", 8);
- vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap);
- char_array_0(buffer);
+ vsnprintf(buffer+8, len+1, format, ap);
+
+ snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK);
+ char_array_0(p);
zero(iov);
IOVEC_SET_STRING(iov[0], buffer);
@@ -478,9 +504,11 @@ _public_ int sd_journal_print_with_location(int priority, const char *file, cons
}
_public_ int sd_journal_printv_with_location(int priority, const char *file, const char *line, const char *func, const char *format, va_list ap) {
- char buffer[8 + LINE_MAX], p[11];
+ char p[11], *buffer = NULL;
struct iovec iov[5];
char *f;
+ int len = 0;
+ rlim_t sts = RLIM_INFINITY;
if (priority < 0 || priority > 7)
return -EINVAL;
@@ -488,12 +516,37 @@ _public_ int sd_journal_printv_with_location(int priority, const char *file, con
if (_unlikely_(!format))
return -EINVAL;
- snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK);
- char_array_0(p);
+ {
+ va_list aq;
+ va_copy(aq, ap);
+ len = vsnprintf(NULL, 0, format, aq);
+ va_end(aq);
+ }
+ if (len <= 0)
+ return -EINVAL;
+
+ sts = stack_size_guess();
+
+ /* Limit the maximum size to the send buffer minus some
+ bytes for the rest
+ */
+ if (sts == RLIM_INFINITY)
+ sts = SNDBUF_SIZE - 1024;
+
+ /* Spare at least one page_size of stack */
+ if (sts < (unsigned)(len + page_size()))
+ len = sts - page_size();
+
+ if (len < 0)
+ return -ENOMEM;
+
+ buffer = alloca(len + 9);
memcpy(buffer, "MESSAGE=", 8);
- vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap);
- char_array_0(buffer);
+ vsnprintf(buffer+8, len+1, format, ap);
+
+ snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK);
+ char_array_0(p);
/* func is initialized from __func__ which is not a macro, but
* a static const char[], hence cannot easily be prefixed with
diff --git a/src/journal/test-journal-send.c b/src/journal/test-journal-send.c
index 3e986ed..b2ff422 100644
--- a/src/journal/test-journal-send.c
+++ b/src/journal/test-journal-send.c
@@ -22,34 +22,66 @@
#include <systemd/sd-journal.h>
#include <stdlib.h>
#include <unistd.h>
-
+#include <stdio.h>
+#include <sys/resource.h>
#include "log.h"
+#define HUGE_SIZE (4096*1024)
+
+static int huge_message_send(void)
+{
+ char *huge;
+ int r;
+ int asz = random() % (long int)sysconf(_SC_PAGESIZE);
+ huge = alloca(asz);
+ memset(huge, 'x', asz-1);
+ huge[asz-1] = 0;
+ r = sd_journal_print(LOG_NOTICE, "huge_message_send: %s", huge);
+ if (r)
+ return r;
+
+ r = huge_message_send();
+ return r;
+}
+
+
int main(int argc, char *argv[]) {
- char huge[4096*1024];
+ int r;
+ char huge[HUGE_SIZE];
+ struct rlimit rlim;
log_set_max_level(LOG_DEBUG);
- sd_journal_print(LOG_INFO, "piepapo");
+ r = sd_journal_print(LOG_INFO, "piepapo");
+ if (r != 0)
+ return 1;
- sd_journal_send("MESSAGE=foobar",
+ r = sd_journal_send("MESSAGE=foobar",
"VALUE=%i", 7,
NULL);
+ if (r != 0)
+ return 1;
errno = ENOENT;
- sd_journal_perror("Foobar");
+ r = sd_journal_perror("Foobar");
+ if (r != 0)
+ return 1;
- sd_journal_perror("");
+ r = sd_journal_perror("");
+ if (r != 0)
+ return 1;
memset(huge, 'x', sizeof(huge));
memcpy(huge, "HUGE=", 5);
char_array_0(huge);
- sd_journal_send("MESSAGE=Huge field attached",
+ r = sd_journal_send("MESSAGE=Huge field attached",
huge,
NULL);
+ if (r != 0)
+ return 1;
- sd_journal_send("MESSAGE=uiui",
+ r = sd_journal_send("MESSAGE=uiui",
"VALUE=A",
"VALUE=B",
"VALUE=C",
@@ -58,12 +90,16 @@ int main(int argc, char *argv[]) {
"OTHERVALUE=Y",
"WITH_BINARY=this is a binary value \a",
NULL);
+ if (r != 0)
+ return 1;
syslog(LOG_NOTICE, "Hello World!");
- sd_journal_print(LOG_NOTICE, "Hello World");
+ r = sd_journal_print(LOG_NOTICE, "Hello World!");
+ if (r != 0)
+ return 1;
- sd_journal_send("MESSAGE=Hello World!",
+ r = sd_journal_send("MESSAGE=Hello World!",
"MESSAGE_ID=52fb62f99e2c49d89cfbf9d6de5e3555",
"PRIORITY=5",
"HOME=%s", getenv("HOME"),
@@ -71,8 +107,40 @@ int main(int argc, char *argv[]) {
"PAGE_SIZE=%li", sysconf(_SC_PAGESIZE),
"N_CPUS=%li", sysconf(_SC_NPROCESSORS_ONLN),
NULL);
-
- sleep(10);
+ if (r != 0)
+ return 1;
+
+ r = sd_journal_print(LOG_NOTICE, "huge string: %s", huge);
+ if (r != 0)
+ return 1;
+
+ r = getrlimit(RLIMIT_STACK, &rlim);
+ if (r) {
+ perror("getrlimit");
+ return 1;
+ }
+
+ rlim.rlim_cur = (rlim_t)sysconf(_SC_PAGESIZE) * 100;
+ r = setrlimit(RLIMIT_STACK, &rlim);
+ if (r) {
+ perror("setrlimit");
+ return 1;
+ }
+
+ r = sd_journal_print(LOG_NOTICE, "huge string: %s", huge);
+ if (r != -ENOMEM)
+ return 1;
+
+ rlim.rlim_cur = (rlim_t)sysconf(_SC_PAGESIZE) * 100 + HUGE_SIZE;
+ r = setrlimit(RLIMIT_STACK, &rlim);
+ if (r) {
+ perror("setrlimit");
+ return 1;
+ }
+
+ r = huge_message_send();
+ if (r != -ENOMEM)
+ return 1;
return 0;
}
--
1.8.2
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