commit e1833e54a76a6fdfda845c22412e68bcdf3e264a
author zijunzhao <zijunzhao@google.com> Wed Apr 26 21:43:30 2023 +0000
committer zijunzhao <zijunzhao@google.com> Wed Apr 26 23:14:36 2023 +0000
tree 623a0dea1b880a5a00184cad943430e7bea9e544
parent a89765bcaa7f7b20804ac761b1ac5cb8441529f9

Set __BIONIC_COMPLICATED_NULLNESS for the vsnprintf family

When annotating the netinet directory aosp/2552567, we realize the
argment s for vsnprintf family can be null only if the buffer size is 0.
So we correct them and add some tests to verify our assumption.

Bugs: b/245972273
Test: adb shell
Change-Id: I51063286272be0daee0d7c1453a374b1f5674481

libc/include/stdio.h

diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index e748faa..d7b65e4 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -143,9 +143,9 @@
     (defined(__cplusplus) && __cplusplus <= 201103L)
 char* _Nullable gets(char* _Nonnull __buf) __attribute__((deprecated("gets is unsafe, use fgets instead")));
 #endif
-int sprintf(char* _Nonnull __s, const char* _Nonnull __fmt, ...)
+int sprintf(char* __BIONIC_COMPLICATED_NULLNESS __s, const char* _Nonnull __fmt, ...)
     __printflike(2, 3) __warnattr_strict("sprintf is often misused; please use snprintf");
-int vsprintf(char* _Nonnull __s, const char* _Nonnull __fmt, va_list __args)
+int vsprintf(char* __BIONIC_COMPLICATED_NULLNESS __s, const char* _Nonnull __fmt, va_list __args)
     __printflike(2, 0) __warnattr_strict("vsprintf is often misused; please use vsnprintf");
 char* _Nullable tmpnam(char* _Nullable __s)
     __warnattr("tmpnam is unsafe, use mkstemp or tmpfile instead");
@@ -251,10 +251,10 @@
 FILE* _Nullable tmpfile(void);
 FILE* _Nullable tmpfile64(void) __INTRODUCED_IN(24);
 
-int snprintf(char* _Nullable __buf, size_t __size, const char* _Nonnull __fmt, ...) __printflike(3, 4);
+int snprintf(char* __BIONIC_COMPLICATED_NULLNESS __buf, size_t __size, const char* _Nonnull __fmt, ...) __printflike(3, 4);
 int vfscanf(FILE* _Nonnull __fp, const char* _Nonnull __fmt, va_list __args) __scanflike(2, 0);
 int vscanf(const char* _Nonnull __fmt , va_list __args) __scanflike(1, 0);
-int vsnprintf(char* _Nullable __buf, size_t __size, const char* _Nonnull __fmt, va_list __args) __printflike(3, 0);
+int vsnprintf(char* __BIONIC_COMPLICATED_NULLNESS __buf, size_t __size, const char* _Nonnull __fmt, va_list __args) __printflike(3, 0);
 int vsscanf(const char* _Nonnull __s, const char* _Nonnull __fmt, va_list __args) __scanflike(2, 0);
 
 #define L_ctermid 1024 /* size for ctermid() */