Add the %m GNU extension to printf/wprintf.
And remove the local hack from syslog(3).
Bug: http://b/112776560
Test: ran tests
Change-Id: I5807e729a978df26187ea0ee255bba4ca74220c8
diff --git a/libc/bionic/syslog.cpp b/libc/bionic/syslog.cpp
index d1a0c5b..6b17d26 100644
--- a/libc/bionic/syslog.cpp
+++ b/libc/bionic/syslog.cpp
@@ -49,8 +49,6 @@
}
void vsyslog(int priority, const char* fmt, va_list args) {
- int caller_errno = errno;
-
// Check whether we're supposed to be logging messages of this priority.
if ((syslog_priority_mask & LOG_MASK(LOG_PRI(priority))) == 0) {
return;
@@ -75,48 +73,10 @@
android_log_priority = ANDROID_LOG_DEBUG;
}
- // glibc's printf family support %m directly, but our BSD-based one doesn't.
- // If the format string seems to contain "%m", rewrite it.
- const char* log_fmt = fmt;
- if (strstr(fmt, "%m") != nullptr) {
- size_t dst_len = 1024;
- char* dst = reinterpret_cast<char*>(malloc(dst_len));
- log_fmt = dst;
-
- const char* src = fmt;
- for (; dst_len > 0 && *src != '\0'; ++src) {
- if (*src == '%' && *(src + 1) == 'm') {
- // Expand %m.
- size_t n = strlcpy(dst, strerror(caller_errno), dst_len);
- if (n >= dst_len) {
- n = dst_len;
- }
- dst += n;
- dst_len -= n;
- ++src;
- } else if (*src == '%' && *(src + 1) == '%') {
- // We need to copy pairs of '%'s so the %m test works.
- if (dst_len <= 2) {
- break;
- }
- *dst++ = '%'; --dst_len;
- *dst++ = '%'; --dst_len;
- ++src;
- } else {
- *dst++ = *src; --dst_len;
- }
- }
- *dst = '\0';
- }
-
// We can't let async_safe_format_log do the formatting because it doesn't support
// all the printf functionality.
char log_line[1024];
- vsnprintf(log_line, sizeof(log_line), log_fmt, args);
-
- if (log_fmt != fmt) {
- free(const_cast<char*>(log_fmt));
- }
+ vsnprintf(log_line, sizeof(log_line), fmt, args);
async_safe_format_log(android_log_priority, log_tag, "%s", log_line);
}
diff --git a/libc/stdio/vfprintf.cpp b/libc/stdio/vfprintf.cpp
index a14963e..8b247e9 100644
--- a/libc/stdio/vfprintf.cpp
+++ b/libc/stdio/vfprintf.cpp
@@ -43,6 +43,7 @@
#include "printf_common.h"
int FUNCTION_NAME(FILE* fp, const CHAR_TYPE* fmt0, va_list ap) {
+ int caller_errno = errno;
int n, n2;
CHAR_TYPE* cp; /* handy char pointer (short term usage) */
CHAR_TYPE sign; /* sign prefix (' ', '+', '-', or \0) */
@@ -451,6 +452,9 @@
break;
case 'n':
__fortify_fatal("%%n not allowed on Android");
+ case 'm':
+ cp = strerror(caller_errno);
+ goto string;
case 'O':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
@@ -493,6 +497,7 @@
} else if ((cp = GETARG(char*)) == nullptr) {
cp = const_cast<char*>("(null)");
}
+ string:
if (prec >= 0) {
size = CHAR_TYPE_STRNLEN(cp, prec);
} else {
diff --git a/libc/stdio/vfwprintf.cpp b/libc/stdio/vfwprintf.cpp
index 1c3b80d..19cce17 100644
--- a/libc/stdio/vfwprintf.cpp
+++ b/libc/stdio/vfwprintf.cpp
@@ -43,6 +43,7 @@
#include "printf_common.h"
int FUNCTION_NAME(FILE* fp, const CHAR_TYPE* fmt0, va_list ap) {
+ int caller_errno = errno;
int n, n2;
CHAR_TYPE* cp; /* handy char pointer (short term usage) */
CHAR_TYPE sign; /* sign prefix (' ', '+', '-', or \0) */
@@ -436,6 +437,16 @@
break;
case 'n':
__fortify_fatal("%%n not allowed on Android");
+ case 'm':
+ free(convbuf);
+ convbuf = helpers::mbsconv(strerror(caller_errno), prec);
+ if (convbuf == nullptr) {
+ fp->_flags |= __SERR;
+ goto error;
+ } else {
+ cp = convbuf;
+ }
+ goto string;
case 'O':
flags |= LONGINT;
__BIONIC_FALLTHROUGH;
@@ -474,6 +485,7 @@
cp = convbuf;
}
}
+ string:
if (prec >= 0) {
size = CHAR_TYPE_STRNLEN(cp, prec);
} else {