Quick and dirty file api

build.py

@@ -123,10 +123,8 @@ try:
         ciabatta_header.write('\n')
         ciabatta_header.write('// This file is AUTO-GENERATED by library.json\n')
         ciabatta_header.write('\n')
-        # Write includes
-        for include in library_config['includes']:
-            ciabatta_header.write(f'#include <{include}>\n')
-        ciabatta_header.write('\n')
+        # Write main include
+        ciabatta_header.write('#include <cia-def.h>\n')
         # Write platform includes
         platform_config = None
         for platform in library_config['platforms']:
@@ -138,10 +136,14 @@ try:
             include_path = os.path.join(platform_config['path'], include)
             ciabatta_header.write(f'#include "{include_path}"\n')
         ciabatta_header.write(f'#include "{target}/tinyrt-iface.h"\n')
-        ciabatta_header.write(f'#include "tinyrt.h"\n')
+        ciabatta_header.write(f'#include <tinyrt.h>\n')
         for tinyrt_source in platform_config['tinyrt']:
             ciabatta_header.write(f'#include "{target}/{tinyrt_source}"\n')
-        # Write API includes
+        # Write module includes
+        for include in library_config['includes']:
+            ciabatta_header.write(f'#include <{include}>\n')
+        ciabatta_header.write('\n')
+        # Write module sources
         ciabatta_header.write('\n')
         for api in library_config['apis']:
             api_name = api['name']

include/stdio.h

@@ -0,0 +1,25 @@
+
+#pragma once
+
+#include <cia-def.h>
+#include <tinyrt.h>
+
+typedef u64 size_t;
+
+typedef struct FILE FILE;
+struct FILE {
+    _RT_File rt_file;
+};
+
+#define EOF (-1)
+
+extern FILE *stdin;
+extern FILE *stdout;
+extern FILE *stderr;
+
+FILE *fopen(const char *restrict filename, const char *restrict mode);
+int fgetc(FILE *file);
+int fputc(int c, FILE *file);
+size_t fread(void *restrict buf, size_t size, size_t count, FILE *restrict file);
+size_t fwrite(void const *restrict buf, size_t size, size_t count, FILE *restrict file);
+int fclose(FILE *file);

include/tinyrt.h

@@ -50,16 +50,20 @@ static _RT_Status _rt_deinit();
 #endif
 
 // File API
-#if _RT_API_FILE == 1
-    struct _RT_File typedef _RT_File;
-    struct _RT_File {
-        union {
-            void *handle;
-            u64 fd;
-        };
-        i32 flags;
+struct _RT_File typedef _RT_File;
+struct _RT_File {
+    union {
+        void *handle;
+        u64 fd;
     };
-    static _RT_Status _rt_file_open(_RT_File *file, char *name, int flags);
+    i32 flags;
+};
+#if _RT_API_FILE == 1
+    static _RT_File _rt_file_stdin;
+    static _RT_File _rt_file_stdout;
+    static _RT_File _rt_file_stderr;
+    static _RT_Status _rt_file_std_handles_init();
+    static _RT_Status _rt_file_open(_RT_File *file, char const *name, int flags);
     static _RT_Status _rt_file_read(u64 size, void *buffer, _RT_File *from, u64 *out_bytes_read);
     static _RT_Status _rt_file_write(_RT_File *to, u64 size, void *buffer, u64 *out_bytes_written);
     static _RT_Status _rt_file_close(_RT_File *file);

src/impl/stdlib-file/file.c

@@ -0,0 +1,85 @@
+
+FILE *stdin;
+FILE *stdout;
+FILE *stderr;
+
+// TODO: memory allocation
+static FILE _files[64];
+static int _files_cnt = 0;
+
+static void _fileapi_init() {
+    _rt_file_std_handles_init();
+    stdin = &_files[_files_cnt++];
+    stdin->rt_file = _rt_file_stdin;
+    stdout = &_files[_files_cnt++];
+    stdout->rt_file = _rt_file_stdout;
+    stderr = &_files[_files_cnt++];
+    stderr->rt_file = _rt_file_stderr;
+}
+
+FILE *fopen(char const *restrict filename, char const *restrict mode) {
+    _RT_File rt_file;
+    int flags = 0;
+    while(*mode) {
+        if(*mode == 'r') flags |= _RT_FILE_READ;
+        if(*mode == 'w') flags |= _RT_FILE_WRITE;
+        // TODO: other flags
+        mode += 1;
+    }
+    _RT_Status status = _rt_file_open(&rt_file, filename, flags);
+    if(status != _RT_STATUS_OK) {
+        return NULL;
+    }
+    FILE *file = &_files[_files_cnt];
+    _files_cnt += 1;
+    file->rt_file = rt_file;
+    return file;
+}
+
+int fgetc(FILE *file) {
+    int c = 0;
+    u64 bytes_read;
+    _RT_Status status = _rt_file_read(1, &c, &file->rt_file, &bytes_read);
+    if(status == _RT_STATUS_FILE_EOF) {
+        return EOF;
+    }
+    else if(status != _RT_STATUS_OK) {
+        return EOF;
+    }
+    return c;
+}
+
+int fputc(int c, FILE *file) {
+    u64 bytes_written;
+    _RT_Status status = _rt_file_write(&file->rt_file, 1, &c, &bytes_written);
+    if(status != _RT_STATUS_OK) {
+        return EOF;
+    }
+    return c;
+}
+
+size_t fread(void *restrict buf, size_t size, size_t count, FILE *restrict file) {
+    u64 bytes_read;
+    _RT_Status status = _rt_file_read(size*count, buf, &file->rt_file, &bytes_read);
+    if(status != _RT_STATUS_OK) {
+        return 0;
+    }
+    return bytes_read / size;
+}
+
+size_t fwrite(void const *restrict buf, size_t size, size_t count, FILE *restrict file) {
+    u64 bytes_written;
+    _RT_Status status = _rt_file_write(&file->rt_file, size*count, (void *)buf, &bytes_written);
+    if(status != _RT_STATUS_OK) {
+        return 0;
+    }
+    return bytes_written / size;
+}
+
+int fclose(FILE *file) {
+    _RT_Status status = _rt_file_close(&file->rt_file);
+    if(status != _RT_STATUS_OK) {
+        return EOF;
+    }
+    return 0;
+}

src/library.json

@@ -24,8 +24,8 @@
 //   this module will not be included in the final build
 
 includes: [
-    "cia-def.h",
-    "stdlib.h"
+    "stdlib.h",
+    "stdio.h",
 ],
 
 platforms: [
@@ -60,6 +60,16 @@ apis: [
             "rt_api_program",
         ]
     },
+    {
+        name: "stdlib_file",
+        path: "impl/stdlib-file",
+        includes: [
+            "file.c"
+        ],
+        reqs: [
+            "rt_api_file"
+        ]
+    }
 ]
 
 // END

src/linux/entry.c

@@ -10,6 +10,8 @@ void __stack_chk_fail(void) {
     syscall_exit(1);
 }
 
+static void _fileapi_init();
+
 void __libc_start_main(
     int (*main)(int, char**, char**),
     int argc, char **argv,
@@ -21,6 +23,7 @@ void __libc_start_main(
     // Get the envp
     char **envp = argv + (argc + 1);
     init(argc, argv, envp);
+    _fileapi_init();
     main(argc, argv, envp);
     fini();
     // glibc bug

src/linux/tinyrt.c

@@ -1,7 +1,20 @@
 
 // See src/tinyrt.h file for the interface this file implements
 
-static _RT_Status _rt_file_open(_RT_File *file, char *name, int _rt_flags) {
+static _RT_File _rt_file_stdin;
+static _RT_File _rt_file_stderr;
+
+static _RT_Status _rt_file_std_handles_init() {
+    _rt_file_stdin.fd = 0;
+    _rt_file_stdin.flags = _RT_FILE_READ;
+    _rt_file_stdout.fd = 1;
+    _rt_file_stdout.flags = _RT_FILE_WRITE;
+    _rt_file_stderr.fd = 2;
+    _rt_file_stdout.flags = _RT_FILE_WRITE;
+    return _RT_STATUS_OK;
+}
+
+static _RT_Status _rt_file_open(_RT_File *file, char const *name, int _rt_flags) {
     if((_rt_flags & 0x3) == 0) {
         return _RT_ERROR_BAD_PARAM;
     }

tests/empty.c

@@ -1,22 +1,9 @@
 
 #include <cia-def.h>
-
-#define STDOUT_FILENO 1
-#define SYS_write 1
-
-static __inline i64 __syscall3(i64 n, i64 a1, i64 a2, i64 a3) {
-    i64 ret;
-    __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2),
-                          "d"(a3) : "rcx", "r11", "memory");
-    return ret;
-}
-
-static inline i64 syscall_write(u32 fd, char const *buf, u64 count) {
-    return __syscall3(SYS_write, (i64)fd, (i64)buf, (u64)count);
-}
+#include <stdio.h>
 
 int main(int argc, char **argv, char **envp) {
     char string[] = "Hello, world!\n";
-    syscall_write(STDOUT_FILENO, string, sizeof string);
+    fwrite(string, 1, sizeof string-1, stdout);
     return 0;
 }