[PATCH v2 0/1] MR4976: Draft: tools: Implement strmake() using asprintf().

[Brendan Shanks (＠bshanks)]

--
  v2: tools: Implement strmake() using asprintf().
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/4976

[PATCH v2 1/1] tools: Implement strmake() using asprintf().

[Brendan Shanks]

From: Brendan Shanks <[e-mail]>

---
 tools/tools.h | 52 ++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 39 insertions(+), 13 deletions(-)

diff --git a/tools/tools.h b/tools/tools.h
index be569f801d5..713244ebffe 100644
--- a/tools/tools.h
+++ b/tools/tools.h
@@ -158,6 +158,40 @@ static inline char *xstrdup( const char *str )
     return strcpy( xmalloc( strlen(str)+1 ), str );
 }
 
+static int xvasprintf( char **ret, const char *format, va_list ap ) __attribute__ ((__format__ (__printf__, 2, 0)));
+static inline int xvasprintf( char **ret, const char *fmt, va_list ap )
+{
+#ifdef _WIN32
+    int n;
+    char *p;
+    va_list copy;
+    size_t size = 100;
+
+    for (;;)
+    {
+        p = xmalloc( size );
+        va_copy( copy, ap );
+        n = vsnprintf( p, size, fmt, copy );
+        va_end( copy );
+        if (n == -1) size *= 2;
+        else if ((size_t)n >= size) size = n + 1;
+        else break;
+        free( p );
+    }
+    *ret = p;
+    return n;
+#else
+    int n = vasprintf( ret, fmt, ap );
+
+    if (n == -1)
+    {
+        fprintf( stderr, "Virtual memory exhausted.\n" );
+        exit(1);
+    }
+    return n;
+#endif
+}
+
 static inline bool strendswith( const char *str, const char *end )
 {
     int l = strlen( str );
@@ -168,21 +202,13 @@ static inline bool strendswith( const char *str, const char *end )
 static char *strmake( const char* fmt, ... ) __attribute__ ((__format__ (__printf__, 1, 2)));
 static inline char *strmake( const char* fmt, ... )
 {
-    int n;
-    size_t size = 100;
     va_list ap;
+    char *ret;
 
-    for (;;)
-    {
-        char *p = xmalloc( size );
-        va_start( ap, fmt );
-	n = vsnprintf( p, size, fmt, ap );
-	va_end( ap );
-        if (n == -1) size *= 2;
-        else if ((size_t)n >= size) size = n + 1;
-        else return p;
-        free( p );
-    }
+    va_start( ap, fmt );
+    xvasprintf( &ret, fmt, ap );
+    va_end( ap );
+    return ret;
 }
 
 /* generic array functions */
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/4976

[Brendan Shanks (＠bshanks)]

On Sat Jan 17 00:45:41 2026 +0000, Brendan Shanks wrote:
> Marking this as a draft for now. Older glibc versions require
> `_GNU_SOURCE` to be defined to expose `vasprintf()`. Wine's `config.h`
> does define that, but the `flex`-generated files include `stdio.h`
> before we can include `config.h`. Not sure there's a way to fix that
> other than through compiler flags, and that's not worth the trouble for this.
> I'll revisit this once the build environment is on a newer glibc.
> glibc didn't fix this until 2.38 (July 2023), I think there will be warnings with any glibc older than that. I think we need to wait a few more years on this.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/4976#note_127257