refactor(sstream): 使用scc_snprintf替换snprintf_

日志格式化函数从snprintf_更改为scc_snprintf以保持一致性，
并调整代码格式以适应新的函数调用方式。

refactor(runtime): 实现平台抽象层(PAL)

引入scc_core_pal.h作为平台抽象层，将内存管理、IO操作和
文件系统功能抽象化。原有的scc_malloc等函数现在通过宏定义
映射到对应的scc_pal_*函数。

feat(runtime): 添加字符串断言检查

在scc_cstring_append_cstr函数中添加Assert(str->data != null)
断言，确保字符串数据指针不为空。

refactor(runtime): 重新组织核心实现文件结构

将原有的cfg.std_impl.c拆分为core_impl.c中的具体实现和
scc_core_pal.h中的抽象接口定义，提供标准库的具体实现。

runtime/scc_core/include/scc_core_impl.h

@@ -1,21 +1,21 @@
 #ifndef __SCC_CORE_IMPL_H__
 #define __SCC_CORE_IMPL_H__
 
+#include "scc_core_pal.h"
 #include "scc_core_type.h"
 
-void *scc_malloc(usize size);
-void *scc_calloc(usize count, usize size);
-void *scc_realloc(void *ptr, usize new_size);
-void scc_free(void *ptr);
-
-typedef struct scc_file *scc_file_t;
+#define scc_malloc scc_pal_malloc
+#define scc_calloc scc_pal_calloc
+#define scc_realloc scc_pal_realloc
+#define scc_free scc_pal_free
+#define scc_exit scc_pal_exit
 
+typedef void *scc_file_t;
 typedef enum {
-    SCC_FILE_READ,  /* 读取源文件、头文件 */
-    SCC_FILE_WRITE, /* 写入目标文件、汇编文件 */
-    SCC_FILE_APPEND /* 日志、调试输出 */
+    SCC_FILE_READ,
+    SCC_FILE_WRITE,
+    SCC_FILE_APPEND,
 } scc_fmode_t;
-
 scc_file_t scc_fopen(const char *path, scc_fmode_t mode);
 void scc_fclose(scc_file_t file);
 usize scc_fsize(scc_file_t file);
@@ -23,20 +23,11 @@ usize scc_fread(scc_file_t file, void *buffer, usize size);
 usize scc_fwrite(scc_file_t file, const void *buffer, usize size);
 cbool scc_fexists(const char *path);
 
-#include "printf/printf.h"
-#define scc_snprintf snprintf_
-#define scc_vsnprintf vsnprintf_
-#ifdef __SCC_CORE_FMT_IMPL__
-#include "printf/printf.c"
-#endif
-
-/* 标准输出 - 用于编译进度、结果 */
-void scc_printf(const char *format, ...);
-
-/* 错误输出 - 用于错误信息、警告 */
-void scc_eprintf(const char *format, ...);
-
-/* 程序控制 */
-void scc_exit(int code);
+int scc_printf(const char *format, ...);
+int scc_eprintf(const char *format, ...);
+int scc_fprintf(scc_file_t file, const char *format, ...);
+int scc_vfprintf(scc_file_t file, const char *format, va_list args);
+int scc_snprintf(char *buff, usize buff_size, const char *fmt, ...);
+int scc_vsnprintf(char *buff, usize buff_size, const char *fmt, va_list args);
 
 #endif /* __SCC_CORE_IMPL_H__ */

runtime/scc_core/include/scc_core_pal.h

@@ -0,0 +1,50 @@
+#ifndef __SCC_CORE_PAL_H__
+#define __SCC_CORE_PAL_H__
+// PAL, platform abstraction layer
+
+#include <stddef.h>
+
+/* Memory */
+
+// Required
+void *scc_pal_malloc(size_t size);
+void *scc_pal_calloc(size_t count, size_t size);
+void *scc_pal_realloc(void *ptr, size_t new_size);
+void scc_pal_free(void *ptr);
+
+/* Exit */
+
+// Required
+void scc_pal_exit(int code);
+
+/* IO */
+
+// Required
+void scc_pal_putchar(char c);
+
+// Option
+void scc_pal_eputchar(char c);
+
+// Option
+void scc_pal_write(const char *data, size_t len);
+
+// Option
+void scc_pal_ewrite(const char *data, size_t len);
+
+/* File */
+
+typedef void *scc_pal_file_t;
+scc_pal_file_t scc_pal_fopen(const char *path);
+void scc_pal_fclose(scc_pal_file_t f);
+size_t scc_pal_fread(scc_pal_file_t f, void *buf, size_t size);
+size_t scc_pal_fwrite(scc_pal_file_t f, const void *buf, size_t size);
+size_t scc_pal_ftell(scc_pal_file_t f);
+enum scc_pal_seek_type {
+    SCC_SEEK_PAL_CUR,
+    SCC_SEEK_PAL_END,
+    SCC_SEEK_PAL_SET,
+};
+size_t scc_pal_fseek(scc_pal_file_t f, size_t offset,
+                     enum scc_pal_seek_type whence);
+
+#endif /* __SCC_CORE_PAL_H__ */

runtime/scc_core/include/scc_core_str.h

@@ -117,6 +117,7 @@ static inline void scc_cstring_append_cstr(scc_cstring_t *str, const char *data,
 
     scc_memcpy(str->data + str->size - 1, data, len);
     str->size += len;
+    Assert(str->data != null);
     str->data[str->size - 1] = '\0'; // 保证 C 字符串兼容性
 }
 

runtime/scc_core/src/cfg.std_impl.c

@@ -2,13 +2,7 @@
 #define _CRT_SECURE_NO_WARNINGS
 #endif
 
-#define __SCC_CORE_FMT_IMPL__
-#include <scc_core_impl.h>
-#define __SCC_LOG_IMPL_IMPORT_SRC__
-#define log_vsnprintf vsnprintf_
-#define log_puts(str) scc_printf("%s", str)
-#define log_exit scc_exit
-#include <log.h>
+#include <scc_core_pal.h>
 
 #include <ctype.h>
 #include <stdarg.h>
@@ -16,91 +10,73 @@
 #include <stdlib.h>
 #include <string.h>
 
-void putchar_(char c) { putchar(c); }
-/* ====== 内存管理核心接口实现 ====== */
+void *scc_pal_malloc(size_t size) { return malloc(size); }
 
-void *scc_malloc(usize size) { return malloc(size); }
+void *scc_pal_calloc(size_t count, size_t size) { return calloc(count, size); }
 
-void *scc_calloc(usize count, usize size) { return calloc(count, size); }
-
-void *scc_realloc(void *ptr, usize new_size) { return realloc(ptr, new_size); }
-
-void scc_free(void *ptr) { free(ptr); }
-
-/* ====== 文件系统核心接口实现 ====== */
-
-static const char *get_file_mode_string(scc_fmode_t mode) {
-    switch (mode) {
-    case SCC_FILE_READ:
-        return "rb";
-    case SCC_FILE_WRITE:
-        return "wb";
-    case SCC_FILE_APPEND:
-        return "ab";
-    default:
-        return "rb";
-    }
+void *scc_pal_realloc(void *ptr, size_t new_size) {
+    return realloc(ptr, new_size);
 }
 
-scc_file_t scc_fopen(const char *path, scc_fmode_t mode) {
-    const char *mode_str = get_file_mode_string(mode);
-    return (scc_file_t)fopen(path, mode_str);
+void scc_pal_free(void *ptr) { free(ptr); }
+
+scc_pal_file_t scc_pal_fopen(const char *path) {
+    return (scc_pal_file_t)fopen(path, "r+b");
 }
 
-void scc_fclose(scc_file_t file) {
+void scc_pal_fclose(scc_pal_file_t file) {
     if (file) {
         fclose((FILE *)file);
     }
 }
 
-usize scc_fsize(scc_file_t file) {
-    FILE *fp = (FILE *)file;
-    if (fseek(fp, 0, SEEK_END) != 0) {
-        perror("fseek failed");
-        return 0;
-    }
-    usize fsize = ftell(fp);
-    if (fseek(fp, 0, SEEK_SET)) {
-        perror("fseek failed");
-        return 0;
-    }
-    return fsize;
-}
-
-usize scc_fread(scc_file_t file, void *buffer, usize size) {
+size_t scc_pal_fread(scc_pal_file_t file, void *buffer, size_t size) {
     if (!file || !buffer)
         return 0;
     return fread(buffer, 1, size, (FILE *)file);
 }
 
-usize scc_fwrite(scc_file_t file, const void *buffer, usize size) {
-    if (!file || !buffer)
-        return 0;
+size_t scc_pal_fwrite(scc_pal_file_t file, const void *buffer, size_t size) {
     return fwrite(buffer, 1, size, (FILE *)file);
 }
 
-cbool scc_fexists(const char *path) {
-    scc_file_t fp = scc_fopen(path, SCC_FILE_READ);
-    if (!fp)
-        return false;
-    scc_fclose(fp);
-    return true;
+size_t scc_pal_ftell(scc_pal_file_t f) { return ftell((FILE *)f); }
+
+size_t scc_pal_fseek(scc_pal_file_t f, size_t offset,
+                     enum scc_pal_seek_type whence) {
+    int whence_val = 0;
+    switch (whence) {
+    case SCC_SEEK_PAL_CUR:
+        whence_val = SEEK_CUR;
+        break;
+    case SCC_SEEK_PAL_END:
+        whence_val = SEEK_END;
+        break;
+    case SCC_SEEK_PAL_SET:
+        whence_val = SEEK_SET;
+        break;
+    }
+    return fseek(f, offset, whence_val);
 }
 
-void scc_printf(const char *format, ...) {
-    va_list args;
-    va_start(args, format);
-    vfprintf(stdout, format, args);
-    va_end(args);
+void scc_pal_exit(int code) { exit(code); }
+
+void scc_pal_putchar(char c) { putchar(c); }
+
+void scc_pal_eputchar(char c) { fputc(c, stderr); }
+
+void scc_pal_write(const char *data, size_t len) {
+    int res = fputs(data, stdout);
+    if (res != 0) {
+        fprintf(stderr, "\nError writing to stdout [%d]\n", res);
+        scc_pal_exit(1);
+    }
 }
 
-void scc_eprintf(const char *format, ...) {
-    va_list args;
-    va_start(args, format);
-    vfprintf(stderr, format, args);
-    va_end(args);
+void scc_pal_ewrite(const char *data, size_t len) {
+    int res = fputs(data, stderr);
+    if (res != 0) {
+        fprintf(stderr, "\nError writing to stderr [%d]\n", res);
+        scc_pal_exit(1);
+    }
 }
-
-/* ====== 系统核心接口实现 ====== */
-
-void scc_exit(int code) { exit(code); }

runtime/scc_core/src/core_impl.c

@@ -0,0 +1,99 @@
+// IMPLEMENT
+#include <printf/printf.c>
+
+#include <scc_core_impl.h>
+#define __SCC_LOG_IMPL_IMPORT_SRC__
+#include <scc_core_log.h>
+
+#define scc_stdout 1
+#define scc_stderr 2
+
+void putchar_(char ch) { LOG_FATAL("you can't use printf.c directly"); }
+
+scc_file_t scc_fopen(const char *path, scc_fmode_t mode) {
+    return scc_pal_fopen(path);
+}
+
+void scc_fclose(scc_file_t file) { scc_pal_fclose(file); }
+
+usize scc_fread(scc_file_t file, void *buffer, usize size) {
+    return scc_pal_fread(file, buffer, size);
+}
+
+usize scc_fwrite(scc_file_t file, const void *buffer, usize size) {
+    return scc_pal_fwrite(file, buffer, size);
+}
+
+usize scc_fsize(scc_pal_file_t file) {
+    if (scc_pal_fseek(file, 0, SCC_SEEK_PAL_END) != 0) {
+        LOG_ERROR("fseek failed");
+        return 0;
+    }
+    size_t fsize = scc_pal_ftell(file);
+    if (scc_pal_fseek(file, 0, SCC_SEEK_PAL_SET)) {
+        LOG_ERROR("fseek failed");
+        return 0;
+    }
+    return fsize;
+}
+
+cbool scc_fexists(const char *path) {
+    scc_file_t fp = scc_fopen(path, SCC_FILE_READ);
+    if (!fp)
+        return false;
+    scc_fclose(fp);
+    return true;
+}
+
+int scc_printf(const char *format, ...) {
+    int ret = 0;
+    va_list args;
+    va_start(args, format);
+    ret = scc_vfprintf((scc_file_t)scc_stdout, format, args);
+    va_end(args);
+    return ret;
+}
+
+int scc_eprintf(const char *format, ...) {
+    int ret = 0;
+    va_list args;
+    va_start(args, format);
+    ret = scc_vfprintf((scc_file_t)scc_stderr, format, args);
+    va_end(args);
+    return ret;
+}
+
+int scc_fprintf(scc_file_t file, const char *format, ...) {
+    int ret = 0;
+    va_list args;
+    va_start(args, format);
+    ret = scc_vfprintf(file, format, args);
+    va_end(args);
+    return ret;
+}
+
+int scc_vfprintf(scc_file_t file, const char *format, va_list args) {
+    char buf[4096] = {0};
+    int size = vsnprintf_(buf, sizeof(buf), format, args);
+    if (file == (scc_file_t)scc_stdout) {
+        scc_pal_write(buf, size);
+    } else if (file == (scc_file_t)scc_stderr) {
+        scc_pal_ewrite(buf, size);
+    } else {
+        scc_pal_fwrite(file, buf, size);
+    }
+    return size;
+}
+
+int scc_snprintf(char *buff, usize buff_size, const char *fmt, ...) {
+    int ret;
+    va_list args;
+    va_start(args, fmt);
+    ret = vsnprintf_(buff, buff_size, fmt, args);
+    va_end(args);
+    return ret;
+}
+
+int scc_vsnprintf(char *buff, usize buff_size, const char *fmt, va_list args) {
+    return vsnprintf_(buff, buff_size, fmt, args);
+}