lib: c: io: implement standard FILE and DIR interfaces

lib/libc/include/dirent.h

@@ -1,6 +1,8 @@
 #ifndef DIRENT_H_
 #define DIRENT_H_
 
+#include <sys/types.h>
+
 #define DT_UNKNOWN 0
 #define DT_BLK     1
 #define DT_CHR     2
@@ -10,4 +12,22 @@
 #define DT_REG     6
 #define DT_SOCK    7
 
+struct dirent {
+	ino_t d_ino;
+	off_t d_off;
+	unsigned short d_reclen;
+	unsigned char d_type;
+	char d_name[256];
+};
+
+struct __opaque_dir;
+typedef struct __opaque_dir DIR;
+
+extern DIR *opendir(const char *name);
+extern DIR *fdopendir(int fd);
+
+extern int closedir(DIR *dirp);
+
+extern struct dirent *readdir(DIR *dirp);
+
 #endif

lib/libc/include/stdio.h

@@ -4,10 +4,15 @@
 #include <stdarg.h>
 #include <stddef.h>
 
+#define EOF -1
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+struct __opaque_file;
+typedef struct __opaque_file FILE;
+
 extern int snprintf(char *buffer, size_t count, const char *format, ...);
 extern int vsnprintf(
 	char *buffer,
@@ -15,6 +20,30 @@ extern int vsnprintf(
 	const char *format,
 	va_list va);
 
+extern FILE *fopen(const char *path, const char *mode);
+extern int fclose(FILE *stream);
+
+extern int feof(FILE *stream);
+extern int ferr(FILE *stream);
+
+extern size_t fread(void *buf, size_t size, size_t count, FILE *stream);
+extern size_t fwrite(const void *buf, size_t size, size_t count, FILE *stream);
+
+extern int fgetc(FILE *stream);
+static inline int getc(FILE *stream)
+{
+	return fgetc(stream);
+}
+
+extern int fputc(int c, FILE *stream);
+static inline int putc(int c, FILE *stream)
+{
+	return fputc(c, stream);
+}
+
+extern char *fgets(char *restrict str, int count, FILE *restrict stream);
+extern int fputs(const char *restrict str, FILE *restrict stream);
+
 #ifdef __cplusplus
 }
 #endif

lib/libc/include/sys/types.h

@@ -7,6 +7,8 @@
 #define SEEK_CUR 1
 #define SEEK_END 2
 
+typedef size_t ino_t;
+
 struct dentry {
 	unsigned long d_ino;
 	unsigned short d_reclen;