Added gfxRealloc()

4 files changed, 40 insertions, 0 deletions

diff --git a/include/gos/chibios.h b/include/gos/chibios.h
index 5193d506..cfbc049e 100644
--- a/include/gos/chibios.h
+++ b/include/gos/chibios.h
@@ -76,6 +76,7 @@ extern "C" {
 #define gfxMutexDestroy(pmutex)		{}
 #define gfxMutexEnter(pmutex)		chMtxLock(pmutex)
 #define gfxMutexExit(pmutex)		chMtxUnlock()
+void *gfxRealloc(void *ptr, size_t oldsz, size_t newsz);
 void gfxSleepMilliseconds(delaytime_t ms);
 void gfxSleepMicroseconds(delaytime_t ms);
 void gfxSemInit(gfxSem *psem, semcount_t val, semcount_t limit);
diff --git a/include/gos/gos.h b/include/gos/gos.h
index fe45ce60..84a2fd0a 100644
--- a/include/gos/gos.h
+++ b/include/gos/gos.h
@@ -128,6 +128,26 @@
 	void *gfxAlloc(size_t sz);
 
 	/**
+	 * @brief	Re-allocate memory
+	 * @return	A pointer to the new memory area or NULL if there is no more memory available
+	 *
+	 * @param[in] ptr		The old memory area to be increased/decreased in size
+	 * @param[in] oldsz		The size in bytes of the old memory area
+	 * @param[in] newsz		The size in bytes of the new memory area
+	 *
+	 * @note		Some operating systems don't use the oldsz parameter as they implicitly know the size of
+	 * 				old memory area. The parameter must always be supplied however for API compatibility.
+	 * @note		gfxRealloc() can make the area smaller or larger but may have to return a different pointer.
+	 * 				If this occurs the new area contains a copy of the data from the old area. The old memory
+	 * 				pointer should not be used after this routine as the original area may have been freed.
+	 * @note		If there is insufficient memory to create the new memory region, NULL is returned and the
+	 * 				old memory area is left unchanged.
+	 *
+	 * @api
+	 */
+	void *gfxRealloc(void *ptr, size_t oldsz, size_t newsz);
+
+	/**
 	 * @brief	Free memory
 	 *
 	 * @param[in] ptr	The memory to free
diff --git a/include/gos/win32.h b/include/gos/win32.h
index fbb45d9b..a8dd6d6f 100644
--- a/include/gos/win32.h
+++ b/include/gos/win32.h
@@ -55,6 +55,7 @@ typedef HANDLE gfxThreadHandle;
 
 #define gfxExit()						ExitProcess(0)
 #define gfxAlloc(sz)					malloc(sz)
+#define gfxRealloc(p,osz,nsz)			realloc(p, nsz)
 #define gfxFree(ptr)					free(ptr)
 #define gfxSleepMilliseconds(ms)		Sleep(ms)
 #define gfxYield()						Sleep(0)
diff --git a/src/gos/chibios.c b/src/gos/chibios.c
index 6ce06d94..0b501110 100644
--- a/src/gos/chibios.c
+++ b/src/gos/chibios.c
@@ -13,6 +13,8 @@
 
 #if GFX_USE_OS_CHIBIOS
 
+#include <string.h>
+
 #if !CH_USE_MUTEXES
 	#error "GOS: CH_USE_MUTEXES must be defined in chconf.h"
 #endif
@@ -29,6 +31,22 @@ void _gosInit(void) {
 	}
 }
 
+void *gfxRealloc(void *ptr, size_t oldsz, size_t newsz) {
+	void *np;
+
+	if (newsz <= oldsz)
+		return ptr;
+
+	np = gfxAlloc(newsz);
+	if (!np)
+		return 0;
+
+	if (oldsz)
+		memcpy(np, ptr, oldsz);
+
+	return np;
+}
+
 void gfxSleepMilliseconds(delaytime_t ms) {
 	switch(ms) {
 	case TIME_IMMEDIATE:	chThdYield();				return;