Wrote a wrapper for vsnprintf() that calls _vcsprintf()/vsnprintf_s() on Windows, because lol. I'm going to try switching from strcpy() to strncpy() for the other cases; let's see if this works.

common/alloc.c

@@ -7,4 +7,5 @@
 #define sharedbitsPrefix uipriv
 #include "../sharedbits/alloc_impl.h"
 #include "../sharedbits/array_impl.h"
+#include "../sharedbits/strsafe_impl.h"
 #undef sharedbitsPrefix

common/errors.c

@@ -1,8 +1,4 @@
 // 12 may 2019
-// TODO get rid of the need for this (it temporarily silences noise so I can find actual build issues)
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <stdarg.h>
 #include <stdio.h>
 #include "ui.h"
@@ -20,7 +16,7 @@ void uiprivInternalError(const char *fmt, ...)
 	int n;
 
 	va_start(ap, fmt);
-	n = vsnprintf(buf, 256, fmt, ap);
+	n = uiprivVsnprintf(buf, 256, fmt, ap);
 	va_end(ap);
 	if (n < 0)
 		uiprivReportError(internalErrorPrefix, "internal error string has encoding error", internalErrorSuffix, true);
@@ -49,7 +45,7 @@ static void prepareProgrammerError(char *buf, int size, unsigned int which, va_l
 		uiprivInternalError("bad programmer error value %u", which);
 	if (messages[which] == NULL)
 		uiprivInternalError("programmer error %u has no message", which);
-	n = vsnprintf(buf, size, messages[which], ap);
+	n = uiprivVsnprintf(buf, size, messages[which], ap);
 	if (n < 0)
 		uiprivInternalError("programmer error string for %u has encoding error", which);
 	if (n >= size)

common/init.c

@@ -1,8 +1,4 @@
 // 19 april 2019
-// TODO get rid of the need for this (it temporarily silences noise so I can find actual build issues)
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
@@ -39,7 +35,7 @@ bool uiprivInitReturnErrorf(uiInitError *err, const char *msg, ...)
 	va_list ap;
 
 	va_start(ap, msg);
-	n = vsnprintf(err->Message, 256, msg, ap);
+	n = uiprivVsnprintf(err->Message, 256, msg, ap);
 	va_end(ap);
 	if (n < 0)
 		uiprivInternalError("encoding error returning initialization error; this means something is very very wrong with libui itself");

common/uipriv.h

@@ -35,6 +35,7 @@ extern bool uiprivSysCheckThread(void);
 #define uiprivArrayInit(arr, T, nGrow, what) uiprivArrayInitFull(&(arr), sizeof (T), nGrow, what)
 #define uiprivArrayFree(arr) uiprivArrayFreeFull(&(arr))
 #define uiprivArrayAt(arr, T, n) (((T *) (arr.buf)) + (n))
+#include "../sharedbits/strsafe_header.h"
 #undef sharedbitsPrefix
 
 // errors.c

sharedbits/strsafe_header.h

@@ -0,0 +1,7 @@
+// 31 may 2019
+
+#include "start.h"
+
+extern int sharedbitsPrefixName(Vsnprintf)(char *s, size_t n, const char *fmt, va_list ap);
+
+#include "end.h"

sharedbits/strsafe_impl.h

@@ -0,0 +1,26 @@
+// 31 may 2019
+// only requires strsafe_header.h if you don't define sharedbitsStatic as static
+
+#include "start.h"
+
+#ifdef sharedbitsStatic
+sharedbitsStatic
+#endif
+int sharedbitsPrefixName(Vsnprintf)(char *s, size_t n, const char *fmt, va_list ap)
+{
+#ifdef _WIN32
+	int ret;
+
+	if (s == NULL && n == 0)
+		return _vscprintf(fmt, ap);
+	// TODO figure out how to disambiguate between encoding errors (returns negative value; does not have documented errno values), other errors (returns negative value; errno == EINVAL), and truncations (returns -1; does not have documented errno values)
+	ret = vsnprintf_s(s, n, _TRUNCATE, fmt, ap);
+	if (ret == -1)
+		return n;
+	return ret;
+#else
+	return vsnprintf(s, n, fmt, ap);
+#endif
+}
+
+#include "end.h"

test/lib/testing.c

@@ -1,8 +1,4 @@
 // 27 february 2018
-// TODO get rid of the need for this (it temporarily silences noise so I can find actual build issues)
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>

test/lib/testingpriv.c

@@ -1,8 +1,4 @@
 // 19 may 2019
-// TODO get rid of the need for this (it temporarily silences noise so I can find actual build issues)
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -26,11 +22,17 @@ void testingprivInternalError(const char *fmt, ...)
 #include "../../sharedbits/array_impl.h"
 #undef sharedbitsPrefix
 
+#define sharedbitsPrefix testingprivImpl
+#define sharedbitsStatic static
+#include "../../sharedbits/strsafe_impl.h"
+#undef sharedbitsStatic
+#undef sharedbitsPrefix
+
 int testingprivVsnprintf(char *s, size_t n, const char *format, va_list ap)
 {
 	int ret;
 
-	ret = vsnprintf(s, n, format, ap);
+	ret = testingprivImplVsnprintf(s, n, format, ap);
 	if (ret < 0)
 		testingprivInternalError("encoding error in vsnprintf(); this likely means your call to testingTLogf() and the like is invalid");
 	return ret;

test/noinitwrongthread.c

@@ -1,8 +1,4 @@
 // 28 may 2019
-// TODO get rid of the need for this (it temporarily silences noise so I can find actual build issues)
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
 #include <stdlib.h>
 #include <string.h>
 #include "lib/thread.h"