src/hotspot/cpu/x86/vm_version_ext_x86.cpp

rev 50985 : 8206977: Minor improvements of runtime code.
Reviewed-by: coleenp, lfoltan

*** 468,490 ****
  
    return OS_OK;
  }
  
  size_t VM_Version_Ext::cpu_write_support_string(char* const buf, size_t buf_len) {
!   assert(buf != NULL, "buffer is NULL!");
!   assert(buf_len > 0, "buffer len not enough!");
  
    unsigned int flag = 0;
    unsigned int fi = 0;
    size_t       written = 0;
    const char*  prefix = "";
  
  #define WRITE_TO_BUF(string)                                                          \
    {                                                                                   \
      int res = jio_snprintf(&buf[written], buf_len - written, "%s%s", prefix, string); \
!     if (res < 0 || (size_t) res >= buf_len - 1) {                                     \
!       buf[buf_len-1] = '\0';                                                          \
        return buf_len - 1;                                                             \
      }                                                                                 \
      written += res;                                                                   \
      if (prefix[0] == '\0') {                                                          \
        prefix = ", ";                                                                  \
--- 468,489 ----
  
    return OS_OK;
  }
  
  size_t VM_Version_Ext::cpu_write_support_string(char* const buf, size_t buf_len) {
!   guarantee(buf != NULL, "buffer is NULL!");
!   guarantee(buf_len > 0, "buffer len not enough!");
  
    unsigned int flag = 0;
    unsigned int fi = 0;
    size_t       written = 0;
    const char*  prefix = "";
  
  #define WRITE_TO_BUF(string)                                                          \
    {                                                                                   \
      int res = jio_snprintf(&buf[written], buf_len - written, "%s%s", prefix, string); \
!     if (res < 0) {                                                                    \
        return buf_len - 1;                                                             \
      }                                                                                 \
      written += res;                                                                   \
      if (prefix[0] == '\0') {                                                          \
        prefix = ", ";                                                                  \
*** 590,600 ****
      _cpuid_info.ext_cpuid1_ebx,
      _cpuid_info.ext_cpuid1_ecx,
      _cpuid_info.ext_cpuid1_edx);
  
    if (outputLen < 0 || (size_t) outputLen >= buf_len - 1) {
!     buf[buf_len-1] = '\0';
      return OS_ERR;
    }
  
    cpu_write_support_string(&buf[outputLen], buf_len - outputLen);
  
--- 589,599 ----
      _cpuid_info.ext_cpuid1_ebx,
      _cpuid_info.ext_cpuid1_ecx,
      _cpuid_info.ext_cpuid1_edx);
  
    if (outputLen < 0 || (size_t) outputLen >= buf_len - 1) {
!     if (buf_len > 0) { buf[buf_len-1] = '\0'; }
      return OS_ERR;
    }
  
    cpu_write_support_string(&buf[outputLen], buf_len - outputLen);