5 files changed, 105 insertions, 3 deletions

diff --git a/README.md b/README.md
index 9b9a956..f47df41 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,7 @@ At this point, the program will safely crash.
 
 - `FD_CLR`
 - `FD_SET`
+- `asprintf`
 - `bcopy`
 - `bzero`
 - `calloc`
@@ -121,6 +122,7 @@ At this point, the program will safely crash.
 - `umask` 
 - `vfprintf` 
 - `vprintf` 
+- `vasprintf`
 - `vsnprintf`
 - `vsprintf`
 - `wcrtomb`
diff --git a/include/stdio.h b/include/stdio.h
index c6817fa..abdef6c 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -220,6 +220,26 @@ _FORTIFY_FN(vprintf) int vprintf(const char *__f, __builtin_va_list __v)
         return __orig_vprintf(__f, __v);
 #endif
 }
+
+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+#undef vasprintf
+#if __has_builtin(__builtin_vasprintf)
+__diagnose_as_builtin(__builtin_vasprintf, 1, 2, 3)
+#endif
+_FORTIFY_FN(vasprintf) int vasprintf(char **restrict strp, const char *restrict fmt, __builtin_va_list ap)
+{
+#if __has_builtin(__builtin___vasprintf_chk) && USE_NATIVE_CHK
+        return __builtin___vasprintf_chk(_FORTIFY_SOURCE, strp, fmt, ap);
+#else
+        int ret = __orig_vasprintf(strp, fmt, ap);
+        if (ret < 0)
+                *strp = NULL;
+        return ret;
+#endif
+}
+
+
+#endif // defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 #endif  // __clang__
 
 
@@ -312,6 +332,28 @@ _FORTIFY_FN(fprintf) int fprintf(FILE *__s, const char *__f, ...)
 #endif
 }
 
+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+#ifndef __clang__
+#undef asprintf
+__fh_access(read_only, 2)
+__fh_format(printf, 2, 0)
+#if __has_builtin(__builtin_asprintf)
+__diagnose_as_builtin(__builtin_asprintf, 2, 3)
+#endif
+_FORTIFY_FN(asprintf) int asprintf(char **restrict strp, const char *restrict fmt, ...)
+{
+#if __has_builtin(__builtin___asprintf_chk) && USE_NATIVE_CHK
+        return __builtin___asprintf_chk(_FORTIFY_SOURCE, strp, fmt, __builtin_va_arg_pack());
+#else
+        int ret = __orig_asprintf(strp, fmt, __builtin_va_arg_pack());
+        if (ret<0)
+                *strp = NULL;
+        return ret;
+#endif
+}
+#endif // __clang__
+#endif
+
 #pragma GCC diagnostic pop
 #endif /* __has_builtin(__builtin_va_arg_pack) */
 
diff --git a/tests/Makefile b/tests/Makefile
index c18898e..32b17b0 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -1,4 +1,4 @@
-CFLAGS+=-I../include/ -D_FORTIFY_SOURCE=3 -static -O2 -DPEDANTIC_CHECKS
+CFLAGS+=-I../include/ -D_FORTIFY_SOURCE=3 -static -O2 -DPEDANTIC_CHECKS -Wno-format
 
 COMPTIME_TARGETS= \
         test_memcpy_overwrite_under  \
@@ -12,6 +12,7 @@ RUNTIME_TARGETS= \
         test_FD_SET_negative         \
         test_FD_ISSET_SETSIZE        \
         test_FD_ISSET_negative       \
+        test_asprintf                \
         test_bcopy_dynamic_read      \
         test_bcopy_dynamic_write     \
         test_bcopy_static_read       \
@@ -126,11 +127,12 @@ RUNTIME_TARGETS= \
         test_ttyname_r_dynamic       \
         test_ttyname_r_static        \
         test_umask                   \
+        test_vasprintf               \
+        test_vfprintf                \
+        test_vprintf                 \
         test_vsnprintf_dynamic       \
         test_vsnprintf_static        \
         test_vsprintf                \
-        test_vfprintf                \
-        test_vprintf                 \
         test_wcscat_static_write     \
         test_wcscpy_static_write     \
         test_wcsncat_static_write    \
diff --git a/tests/test_asprintf.c b/tests/test_asprintf.c
new file mode 100644
index 0000000..a02d110
--- /dev/null
+++ b/tests/test_asprintf.c
@@ -0,0 +1,20 @@
+#define _GNU_SOURCE
+#include "common.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char** argv) {
+    char* buf;
+    asprintf(&buf, "total: %d+%d=%d", 1, 2, 3);
+    puts(buf);
+    free(buf);
+
+#ifndef __clang__
+    asprintf(&buf, "total: %", 1);
+    assert(buf == NULL);
+#endif
+
+    return 0;
+}
diff --git a/tests/test_vasprintf.c b/tests/test_vasprintf.c
new file mode 100644
index 0000000..2f71714
--- /dev/null
+++ b/tests/test_vasprintf.c
@@ -0,0 +1,36 @@
+#define _GNU_SOURCE
+#include "common.h"
+
+#include <assert.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+void test(const char *fmt, ...)
+{
+    char* buf;
+    va_list args;
+    va_start(args, fmt);
+    vasprintf(&buf, fmt, args);
+    va_end(args);
+    puts(buf);
+    free(buf);
+}
+
+void test2(const char *fmt, ...)
+{
+    char* buf;
+    va_list args;
+    va_start(args, fmt);
+    vasprintf(&buf, fmt, args);
+    va_end(args);
+    assert(buf == NULL);
+}
+
+int main(int argc, char** argv) {
+    test("Total: %d+%d=%d", 1, 2, 3);
+#ifndef __clang__
+    test2("Total: %", 1, 2, 3);
+#endif
+    return 0;
+}