实现

simple_protobuf.h

@@ -0,0 +1,43 @@
+#ifndef _SIMPLE_PROTOBUF_H_
+#define _SIMPLE_PROTOBUF_H_
+
+#include <stdint.h>
+
+struct SIMPLE_PB {
+    uint64_t len;
+    char target[];
+};
+typedef struct SIMPLE_PB SIMPLE_PB;
+
+SIMPLE_PB* get_pb(FILE* fp);
+int set_pb(FILE* fp, uint8_t* items_type, uint64_t struct_len, void* target);
+
+uint8_t first_set(uint64_t n) {
+    uint8_t i = 0;
+    while(!(n & 1)) {
+        n >>= 1;
+        i++;
+    }
+    return i;
+}
+
+void align_struct(uint8_t* items_type, uint64_t items_cnt, uint64_t struct_size) {
+    uint64_t sum = 0;
+    uint64_t min_cnt = 0;
+    uint8_t min = 255;
+    for(uint64_t i = 0; i < items_cnt; i++) {
+        sum += 1u << items_type[i];
+        if(min > items_type[i]) min = items_type[i];
+    }
+    while(sum < struct_size) {
+        uint8_t new_min = 255;
+        sum = 0;
+        for(uint64_t i = 0; i < items_cnt; i++) {
+            if(items_type[i] == min) items_type[i]++;
+            if(new_min > items_type[i]) new_min = items_type[i];
+            sum += 1u << items_type[i];
+        }
+    }
+}
+
+#endif