vulkaninfo: Print human-readable heap sizes

Since the size of a memory heap can be rather substantial, it is helpful
to have the size additionally printed out in a human-readable format,
i.e. using prefixes.

Change-Id: I47aad4fce06471804ce9e853ba300626b6ad34c8

1 files changed, 37 insertions, 1 deletions

diff --git a/demos/vulkaninfo.c b/demos/vulkaninfo.c
index be81c6fd..3e7e133e 100644
--- a/demos/vulkaninfo.c
+++ b/demos/vulkaninfo.c
@@ -20,6 +20,15 @@
  * Author: Mark Lobodzinski <mark@lunarg.com>
  * Author: Rene Lindsay <rene@lunarg.com>
  */
+
+#ifdef __GNUC__
+#ifndef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 200809L
+#endif
+#else
+#define strndup(p, n) strdup(p)
+#endif
+
 #include <assert.h>
 #include <inttypes.h>
 #include <stdbool.h>
@@ -47,6 +56,7 @@
 #ifdef _WIN32
 
 #define snprintf _snprintf
+#define strdup   _strdup
 
 // Returns nonzero if the console is used only for this process. Will return
 // zero if another process (such as cmd.exe) is also attached.
@@ -1312,6 +1322,29 @@ static void AppGpuDumpQueueProps(const struct AppGpu *gpu, uint32_t id) {
     fflush(stdout);
 }
 
+// This prints a number of bytes in a human-readable format according to prefixes of the International System of Quantities (ISQ),
+// defined in ISO/IEC 80000. The prefixes used here are not SI prefixes, but rather the binary prefixes based on powers of 1024
+// (kibi-, mebi-, gibi- etc.).
+#define kBufferSize 32
+
+static char *HumanReadable(const size_t sz) {
+    const char prefixes[] = "KMGTPEZY";
+    char buf[kBufferSize];
+    int which = -1;
+    double result = (double)sz;
+    while (result > 1024 && which < 7) {
+        result /= 1024;
+        ++which;
+    }
+
+    char unit[] = "\0i";
+    if (which >= 0) {
+        unit[0] = prefixes[which];
+    }
+    snprintf(buf, kBufferSize, "%.2f %sB", result, unit);
+    return strndup(buf, kBufferSize);
+}
+
 static void AppGpuDumpMemoryProps(const struct AppGpu *gpu) {
     const VkPhysicalDeviceMemoryProperties *props = &gpu->memory_props;
 
@@ -1339,7 +1372,10 @@ static void AppGpuDumpMemoryProps(const struct AppGpu *gpu) {
     for (uint32_t i = 0; i < props->memoryHeapCount; i++) {
         printf("\tmemoryHeaps[%u] : \n", i);
         const VkDeviceSize memSize = props->memoryHeaps[i].size;
-        printf("\t\tsize          = " PRINTF_SIZE_T_SPECIFIER " (0x%" PRIxLEAST64 ")\n", (size_t)memSize, memSize);
+        char *mem_size_human_readable = HumanReadable((const size_t)memSize);
+        printf("\t\tsize          = " PRINTF_SIZE_T_SPECIFIER " (0x%" PRIxLEAST64 ") (%s)\n", (size_t)memSize, memSize,
+               mem_size_human_readable);
+        free(mem_size_human_readable);
 
         VkMemoryHeapFlags heap_flags = props->memoryHeaps[i].flags;
         printf("\t\tflags: \n\t\t\t");