Added missing DRAM fallback to pvPortCallocIram, pvPortZallocIram, and

pvPortMalloc(,,,true) case. Improved comments.

cores/esp8266/heap.cpp

@@ -395,51 +395,89 @@ void IRAM_ATTR vPortFree(void *ptr, const char* file, int line)
 
  The NON-OS SDK 3.0.x has breaking changes to pvPortMalloc. They added one more
  argument for selecting a heap. To avoid breaking the build, I renamed their
- broken version pvEsprMalloc. To be used, the LIBS need to be edited.
+ breaking version to sdk3_pvPortMalloc. To complete the fix, the LIBS need to
+ be edited.
 
- They also added pvPortZallocIram and pvPortCallocIram, which are not a
- problem.
+ Also in the release are low-level functions pvPortZallocIram and
+ pvPortCallocIram, which are not documented in the Espressif NONOS SDK manual.
+ No issues in providing replacements. For the non-Arduino ESP8266 applications,
+ pvPortZallocIram and pvPortCallocIram would have been selected through the
+ macros like os_malloc defined in `mem.h`.
+
+ OOM - Implementation strategy - Native v3.0 SDK
+ * For functions `pvPortMalloc(,,,true);` and `pvPortMallocIram(,,,);` on a
+ failed IRAM alloc, try DRAM.
+ * For function `pvPortMalloc(,,,false);` use DRAM only - on fail, do not
+ try IRAM.
 
  WPA2 Enterprise connect crashing is fixed at v3.0.2 and up.
 
  Not used for unreleased version NONOSDK3V0.
 */
+#ifdef UMM_HEAP_IRAM
 void* IRAM_ATTR sdk3_pvPortMalloc(size_t size, const char* file, int line, bool iram)
 {
  if (iram) {
  HeapSelectIram ephemeral;
- return heap_pvPortMalloc(size, file, line);
- } else {
+ void* ret = heap_pvPortMalloc(size, file, line);
+ if (ret) return ret;
+ }
+ {
  HeapSelectDram ephemeral;
  return heap_pvPortMalloc(size, file, line);
  }
 }
 
 void* IRAM_ATTR pvPortCallocIram(size_t count, size_t size, const char* file, int line)
 {
- HeapSelectIram ephemeral;
- return heap_pvPortCalloc(count, size, file, line);
+ {
+ HeapSelectIram ephemeral;
+ void* ret = heap_pvPortCalloc(count, size, file, line);
+ if (ret) return ret;
+ }
+ {
+ HeapSelectDram ephemeral;
+ return heap_pvPortCalloc(count, size, file, line);
+ }
 }
 
 void* IRAM_ATTR pvPortZallocIram(size_t size, const char* file, int line)
 {
- HeapSelectIram ephemeral;
- return heap_pvPortZalloc(size, file, line);
+ {
+ HeapSelectIram ephemeral;
+ void* ret = heap_pvPortZalloc(size, file, line);
+ if (ret) return ret;
+ }
+ {
+ HeapSelectDram ephemeral;
+ return heap_pvPortZalloc(size, file, line);
+ }
 }
+#define CONFIG_IRAM_MEMORY 1
 
-/*
- uint32_t IRAM_ATTR user_iram_memory_is_enabled(void)
- {
- return CONFIG_ENABLE_IRAM_MEMORY;
- }
+#else
+// For sdk3_pvPortMalloc, the bool argument is ignored and intentionally omitted.
+extern "C" void* sdk3_pvPortMalloc(size_t size, const char* file, int line) __attribute__ ((alloc_size(1), malloc, nothrow, alias("pvPortMalloc")));
+extern "C" void* pvPortCallocIram(size_t count, size_t size, const char* file, int line) __attribute__((alloc_size(1, 2), malloc, nothrow, alias("pvPortCalloc")));
+extern "C" void* pvPortZallocIram(size_t size, const char* file, int line) __attribute__((alloc_size(1), malloc, nothrow, alias("pvPortZalloc")));
+#define CONFIG_IRAM_MEMORY 0
+#endif // #ifdef UMM_HEAP_IRAM
 
+/*
  We do not need the function user_iram_memory_is_enabled().
  1. It was used by mem_manager.o which was replaced with this custom heap
- implementation. IRAM memory selection is handled differently.
+ implementation. IRAM memory selection is handled differently for
+ Arduino ESP8266.
  2. In libmain.a, Cache_Read_Enable_New uses it for cache size. However, When
  using IRAM for memory or running with 48K IRAM for code, we use a
  replacement Cache_Read_Enable to correct the cache size ignoring
  Cache_Read_Enable_New's selected value.
+ 3. Create a linker conflicts in the event the sketch author tries to control
+ IRAM heap through this method.
 */
-#endif
+uint32 IRAM_ATTR user_iram_memory_is_enabled(void)
+{
+ return CONFIG_IRAM_MEMORY;
+}
+#endif // #if (NONOSDK >= (0x30000))
 };