Added wren limiting fork support

2 files changed, 116 insertions, 0 deletions

diff --git a/src/resources/config.c b/src/resources/config.c
new file mode 100644
index 0000000..05b80cd
--- /dev/null
+++ b/src/resources/config.c
@@ -0,0 +1,100 @@
+#include "resources.h"
+#include <stdlib.h>
+#include <stddef.h>
+#include <raylib.h>
+#include <stdio.h>
+#include <string.h>
+
+Config config = {
+    .MaxOperations = DEFAULT_MAX_OPS,
+};
+
+bool startsWith(const char *str, const char *prefix) {
+    if (str == NULL || prefix == NULL) {
+        return false;
+    }
+
+    size_t prefix_len = strlen(prefix);
+
+    if (strlen(str) < prefix_len) {
+        return false;
+    }
+
+    return strncmp(str, prefix, prefix_len) == 0;
+}
+
+// Strips everything before '=' (including). Does not allocate.
+char *stripName(char *line, size_t len) {
+    if (line == NULL) {
+        return NULL;
+    }
+    
+    for (size_t ptr = 0; ptr < len; ptr++) {
+        if (line[ptr] == '\0') {
+            return NULL; 
+        }
+        if (line[ptr] == '=') {
+            return &line[ptr + 1];
+        }
+    }
+
+    return NULL;
+}
+
+// Reads one line and assigns the param if found
+void evaluateConfigLive(char *line) {
+    size_t len = strlen(line);
+    // Empty lines and comments
+    if (len <= 1 || line[0] == '#') return;
+    // Removing a new line
+    if (line[len-1] == '\n') {
+        line[len-1] = 0x0;
+        len -= 1;
+    }
+
+    if (startsWith(line, "MaxOperations")) {
+        char *value = stripName(line, len);
+
+        char *endptr;
+        unsigned long long parsed = strtoull(value, &endptr, 10);
+        if (value == endptr || *endptr != '\0') {
+            TraceLog(LOG_WARNING, "Failed to parse the value for MaxOperations. Provided value: '%s'", value); 
+            return;
+        }
+        config.MaxOperations = parsed;
+        return;
+    }
+
+}
+
+bool ReadConfig(const char *location) {
+    FILE *file = fopen(location, "r");
+    if (file == NULL) {
+        perror("Failed to open the config file");
+        return false;
+    }
+
+    fseek(file, 0, SEEK_END);
+    long size = ftell(file);
+    rewind(file);
+
+    char* buffer = malloc(size + 1);
+    if (buffer == NULL) {
+        fclose(file);
+        perror("Failed to load the config file");
+        return false;
+    }
+
+
+    while (fgets(buffer, size, file)) {
+        evaluateConfigLive(buffer);
+    }
+
+    free(buffer);
+    fclose(file);
+    return true;
+}
+
+Config *GetConfig() {
+    return &config;
+}
diff --git a/src/resources/resources.h b/src/resources/resources.h
index d3ad840..8f6cd1d 100644
--- a/src/resources/resources.h
+++ b/src/resources/resources.h
@@ -1,8 +1,21 @@
+#include <stddef.h>
 #include <raylib.h>
 
 #ifndef RESOURCES_H
 #define RESOURCES_H
 
+static const size_t DEFAULT_MAX_OPS = 2 * 1000 * 1000;
+static const char *DEFAULT_CONFIG_LOCATION = "config.conf";
+
+typedef struct {
+    // The maximum amount of operations performed by a VM on each check. 
+    //
+    // Keep in mind that setting this parameter higher will make the infinite
+    // loops in your submission longer to detect. Lowering this parameter will make
+    // the limitation on the code runtime stricter.
+    size_t MaxOperations;
+} Config;
+
 void DrawBackground();
 
 /// #670916 as RGBA
@@ -18,6 +31,9 @@ static const Color COLORSCHEME_WHITE = { 233, 225, 185, 255 };
 /// #48A56A as RGBA
 static const Color COLORSCHEME_GREEN = { 72, 165, 106, 255 };
 
+bool ReadConfig(const char *location);
+Config *GetConfig();
+
 void LoadResources();
 Font *GetMainFont();
 Font *GetMonoFont();