improve ini performance

src/ini.c

@@ -0,0 +1,49 @@
+#include <windows.h>
+#include "debug.h"
+#include "config.h"
+#include "crc32.h"
+
+static unsigned long g_ini_section_hashes[1024];
+
+BOOL ini_section_exists(char* section)
+{
+    if (!g_ini_section_hashes[0])
+    {
+        char* buf = calloc(8192, 1);
+        if (buf)
+        {
+            if (GetPrivateProfileSectionNamesA(buf, 8192, g_config.ini_path) > 0)
+            {
+                for (int i = 0; *buf && i < sizeof(g_ini_section_hashes) / sizeof(g_ini_section_hashes[0]); i++)
+                {
+                    size_t len = strlen(buf);
+
+                    for (char* p = buf; *p; ++p) 
+                        *p = tolower(*p);
+
+                    g_ini_section_hashes[i] = Crc32_ComputeBuf(0, buf, len);
+
+                    buf += len + 1;
+                }
+            }
+            
+            free(buf);
+        }
+    }
+
+    char s[MAX_PATH];
+    strncpy(s, section, sizeof(s) - 1);
+
+    for (char* p = s; *p; ++p)
+        *p = tolower(*p);
+
+    unsigned long hash = Crc32_ComputeBuf(0, s, strlen(s));
+
+    for (int i = 0; i < sizeof(g_ini_section_hashes) / sizeof(g_ini_section_hashes[0]) && g_ini_section_hashes[i]; i++)
+    {
+        if (g_ini_section_hashes[i] == hash)
+            return TRUE;
+    }
+
+    return FALSE;
+}