refactor: split up the utilities file into smaller modules

src/object.c

@@ -0,0 +1,117 @@
+#include "object.h"
+
+char* get_object(char* hash, size_t* size_out) {
+    char dir_path[PATH_MAX];
+    char repo_path[PATH_MAX];
+    char file_path[PATH_MAX];
+    snprintf(dir_path, sizeof(dir_path), ".merk/objects/%.2s", hash);
+    snprintf(repo_path, sizeof(repo_path), "%s/%s", dir_path, hash+2);
+    realpath(repo_path, file_path);
+
+    size_t compressed_size;
+    unsigned char* compressed_data = (unsigned char*)get_file_content_with_size(file_path, &compressed_size);
+    if (!compressed_data || compressed_size == 0) {
+        free(compressed_data);
+        return NULL;
+    }
+
+    size_t idx = 0;
+    while (idx < compressed_size && IS_DIGIT(compressed_data[idx])) {
+        idx++;
+    }
+
+    if (idx == 0) {
+        perror("ERROR: no length found at start of object!");
+        free(compressed_data);
+        return NULL;
+    }
+
+    char* size_str = calloc(idx + 1, sizeof(char));
+    if (!size_str) {
+        free(compressed_data);
+        return NULL;
+    }
+
+    memcpy(size_str, compressed_data, idx);
+    size_str[idx] = '\0';
+
+    char* end;
+    long original_size = strtol(size_str, &end, 10);
+    if (end == size_str || *end != '\0') {
+        perror("ERROR: invalid length in get_object!");
+        free(size_str);
+        free(compressed_data);
+        return NULL;
+    }
+    free(size_str);
+
+    if (idx < compressed_size && compressed_data[idx] == ' ') {
+        idx++;
+    }
+
+    char* decompressed = malloc(original_size + 1);
+    if (!decompressed) {
+        free(compressed_data);
+        return NULL;
+    }
+    uLongf decompressed_size = original_size;
+
+    if (uncompress((Bytef*)decompressed, &decompressed_size, compressed_data + idx, compressed_size - idx) != Z_OK) {
+        perror("ERROR: decompression failed in get_object!");
+        free(decompressed);
+        free(compressed_data);
+        return NULL;
+    }
+
+    free(compressed_data);
+
+    decompressed[decompressed_size] = '\0';
+    if (size_out) {
+        *size_out = decompressed_size;
+    }
+
+    return decompressed;
+}
+
+void* parse_object(char* hash, ObjectType type, size_t* size_out) {
+    size_t line_count;
+    char* content = get_object(hash, &line_count);
+    if (!content) return NULL;
+    if (line_count == 0) {
+        free(content);
+        return NULL;
+    }
+
+    switch (type) {
+        case BaseFileObject: {
+            File* file = from_string(content);
+            if (!file) {
+                free(content);
+                return NULL;
+            }
+            free(content);
+            return file;
+        }
+        case TreeObject: {
+            FileInfoBuffer* buffer = file_info_buffer_new();
+            if (!buffer) {
+                free(content);
+                return NULL;
+            }
+
+            if (read_tree(buffer, hash) < 0) {
+                file_info_buffer_free(buffer);
+                free(content);
+                return NULL;
+            }
+
+            free(content);
+            return buffer;
+        }
+        case FileDiffObject: {
+            
+        }
+
+        default: free(content); return NULL;
+    }
+}