本次在实际测试情况下，发现程序无缘无故的异常，导致看门狗超时复位，经过排查是malloc函数分配失败的时候，依然对指针进行了操作，导致异常。以前没重视这个问题是因为，总觉的malloc基本都会成功的，假如循环调用一个函数logOutput，里面有malloc和free，那么下次调用logOutput分配相同的空间应该也是成功的（实际上非我所愿）。问题函数如下，必须对pBuffer没有分配成功做处理，否则很容易出问题。
static inline void logOutput(uint32_t level, const char *tag, const char* format, ...)
{
va_list va;
int len, len2,space;
char* pBuffer;
pBuffer = (char*)malloc(512);
/*space "\n\0"*/
if(pBuffer == NULL)
return;
space = gLogBufferLength - 2;
len = utils_snprintf(pBuffer, LOG_PREFIX_SIZE_MAX, "#%s,%d:", tag,level);
utils_snprintf( pBuffer, LOG_PREFIX_SIZE_MAX, "#%s,%d:", tag,level);
space -= len;
va_start(va, format);
len2 = utils_vsnprintf( pBuffer+len, space ,format, va);
va_end(va);
len += (len2>0?len2:space);
if(len < gLogBufferLength - 2){
pBuffer[len] = ‘\n‘;
pBuffer[len+1] = ‘\0‘;
}else{
pBuffer[gLogBufferLength - 5] = ‘.‘;
pBuffer[gLogBufferLength - 4] = ‘.‘;
pBuffer[gLogBufferLength - 3] = ‘?‘;
pBuffer[gLogBufferLength - 2] = ‘\n‘;
pBuffer[gLogBufferLength - 1] = ‘\0‘;
}
logwrite((uint8_t*)pBuffer,utils_strlen(pBuffer));
free(pBuffer);
};
