banan-os/libc/stdio.cpp

513 lines
7.6 KiB
C++

#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <sys/syscall.h>
#include <unistd.h>
struct FILE
{
int fd { -1 };
off_t offset { 0 };
bool eof { false };
bool error { false };
unsigned char buffer[BUFSIZ];
uint32_t buffer_index { 0 };
};
static FILE s_files[FOPEN_MAX] {
{ .fd = STDIN_FILENO },
{ .fd = STDOUT_FILENO },
{ .fd = STDERR_FILENO },
};
FILE* stdin = &s_files[0];
FILE* stdout = &s_files[1];
FILE* stderr = &s_files[2];
void clearerr(FILE* file)
{
file->eof = false;
file->error = false;
}
char* ctermid(char* buffer)
{
static char s_buffer[L_ctermid];
char* target = buffer ? buffer : s_buffer;
syscall(SYS_TERMID, target);
return target;
}
int fclose(FILE* file)
{
if (int ret = syscall(SYS_CLOSE, file->fd) < 0)
{
errno = -ret;
return EOF;
}
file->fd = -1;
return 0;
}
// TODO
FILE* fdopen(int, const char*);
int feof(FILE* file)
{
return file->eof;
}
int ferror(FILE* file)
{
return file->error;
}
int fflush(FILE* file)
{
if (file == nullptr)
{
for (int i = 0; i < FOPEN_MAX; i++)
if (s_files[i].fd != -1)
if (int ret = fflush(&s_files[i]); ret != 0)
return ret;
return 0;
}
if (file->buffer_index == 0)
return 0;
if (long ret = syscall(SYS_WRITE, file->fd, file->buffer, file->buffer_index); ret < 0)
{
errno = -ret;
file->error = true;
return EOF;
}
file->buffer_index = 0;
return 0;
}
int fgetc(FILE* file)
{
if (file->eof)
return EOF;
unsigned char c;
long ret = syscall(SYS_READ, file->fd, &c, 1);
if (ret < 0)
{
errno = -ret;
return EOF;
}
else if (ret == 0)
{
file->eof = true;
return EOF;
}
file->offset++;
return c;
}
int fgetpos(FILE* file, fpos_t* pos)
{
*pos = file->offset;
return 0;
}
char* fgets(char* str, int size, FILE* file)
{
if (size == 0)
return str;
int c = fgetc(file);
if (c == EOF)
return nullptr;
str[0] = c;
for (int i = 1; i < size - 1; i++)
{
str[i] = fgetc(file);
if (str[i] == EOF)
{
str[i] = '\0';
return nullptr;
}
if (str[i] == '\n')
{
str[i + 1] = '\0';
return str;
}
}
str[size - 1] = '\0';
return str;
}
// TODO
int fileno(FILE*);
// TODO
void flockfile(FILE*);
FILE* fopen(const char* pathname, const char* mode)
{
uint8_t flags = 0;
if (mode[0] == 'r')
flags |= O_RDONLY;
else if (mode[0] == 'b')
flags |= O_WRONLY | O_CREAT | O_TRUNC;
else if (mode[0] == 'a')
flags |= O_WRONLY | O_CREAT | O_APPEND;
else
{
errno = EINVAL;
return nullptr;
}
if (mode[1] && mode[2] && mode[1] == mode[2])
{
errno = EINVAL;
return nullptr;
}
for (int i = 1; i <= 2; i++)
{
if (mode[i] == 0)
break;
else if (mode[i] == '+')
flags |= O_RDWR;
else if (mode[i] == 'b')
continue;
else
{
errno = EINVAL;
return nullptr;
}
}
int fd = open(pathname, flags);
if (fd == -1)
return nullptr;
for (int i = 0; i < FOPEN_MAX; i++)
{
if (s_files[i].fd == -1)
{
s_files[i] = { .fd = fd };
return &s_files[i];
}
}
errno = EMFILE;
return nullptr;
}
int fprintf(FILE* file, const char* format, ...)
{
va_list arguments;
va_start(arguments, format);
int ret = vfprintf(file, format, arguments);
va_end(arguments);
return ret;
}
int fputc(int c, FILE* file)
{
file->buffer[file->buffer_index++] = c;
file->offset++;
if (c == '\n' || file->buffer_index == sizeof(file->buffer))
if (fflush(file) == EOF)
return EOF;
return (unsigned char)c;
}
int fputs(const char* str, FILE* file)
{
while (*str)
{
if (putc(*str, file) == EOF)
return EOF;
str++;
}
return 0;
}
size_t fread(void* buffer, size_t size, size_t nitems, FILE* file)
{
if (file->eof || nitems * size == 0)
return 0;
long ret = syscall(SYS_READ, file->fd, buffer, size * nitems);
if (ret < 0)
{
errno = -ret;
file->error = true;
return 0;
}
if (ret < size * nitems)
file->eof = true;
file->offset += ret;
return ret / size;
}
// TODO
FILE* freopen(const char*, const char*, FILE*);
// TODO
int fscanf(FILE*, const char*, ...);
int fseek(FILE* file, long offset, int whence)
{
return fseeko(file, offset, whence);
}
int fseeko(FILE* file, off_t offset, int whence)
{
if (whence == SEEK_CUR)
file->offset += offset;
else if (whence == SEEK_SET)
file->offset = offset;
else if (whence == SEEK_END)
{
errno = ENOTSUP;
return -1;
}
else
{
errno = EINVAL;
return -1;
}
if (file->offset < 0)
{
file->offset -= offset;
errno = EINVAL;
return -1;
}
if (long ret = syscall(SYS_SEEK, file->fd, file->offset); ret < 0)
{
errno = -ret;
return -1;
}
file->eof = false;
return 0;
}
int fsetpos(FILE* file, const fpos_t* pos)
{
return fseek(file, *pos, SEEK_SET);
}
long ftell(FILE* file)
{
return ftello(file);
}
off_t ftello(FILE* file)
{
return file->offset;
}
// TODO
int ftrylockfile(FILE*);
// TODO
void funlockfile(FILE*);
size_t fwrite(const void* buffer, size_t size, size_t nitems, FILE* file)
{
unsigned char* ubuffer = (unsigned char*)buffer;
for (size_t byte = 0; byte < nitems * size; byte++)
if (fputc(ubuffer[byte], file) == EOF)
return byte / size;
return nitems;
}
int getc(FILE* file)
{
return fgetc(file);
}
int getchar(void)
{
return getc(stdin);
}
// TODO
int getc_unlocked(FILE*);
// TODO
int getchar_unlocked(void);
char* gets(char* buffer)
{
if (stdin->eof)
return nullptr;
unsigned char* ubuffer = (unsigned char*)buffer;
int first = fgetc(stdin);
if (first == EOF)
return nullptr;
*ubuffer++ = first;
for (;;)
{
int c = fgetc(stdin);
if (c == '\n' || c == EOF)
{
*ubuffer++ = '\0';
return buffer;
}
*ubuffer++ = c;
}
}
// TODO
int pclose(FILE*);
void perror(const char* string)
{
if (string && *string)
{
fputs(string, stderr);
fputs(": ", stderr);
}
fputs(strerror(errno), stderr);
fputc('\n', stderr);
stderr->error = true;
}
// TODO
FILE* popen(const char*, const char*);
int printf(const char* format, ...)
{
va_list arguments;
va_start(arguments, format);
int ret = vfprintf(stdout, format, arguments);
va_end(arguments);
return ret;
}
int putc(int c, FILE* file)
{
return fputc(c, file);
}
int putchar(int c)
{
return putc(c, stdout);
}
// TODO
int putc_unlocked(int, FILE*);
// TODO
int putchar_unlocked(int);
int puts(const char* string)
{
if (fputs(string, stdout) == EOF)
return EOF;
if (fputc('\n', stdout) == EOF)
return EOF;
return 0;
}
// TODO
int remove(const char*);
// TODO
int rename(const char*, const char*);
// TODO
void rewind(FILE*);
// TODO
int scanf(const char*, ...);
// TODO
void setbuf(FILE*, char*);
// TODO
int setvbuf(FILE*, char*, int, size_t);
// TODO
int snprintf(char*, size_t, const char*, ...);
// TODO
int sprintf(char*, const char*, ...);
// TODO
int sscanf(const char*, const char*, ...);
// TODO
char* tempnam(const char*, const char*);
// TODO
FILE* tmpfile(void);
// TODO
char* tmpnam(char*);
// TODO
int ungetc(int, FILE*);
int vfprintf(FILE* file, const char* format, va_list arguments)
{
int written = 0;
while (*format)
{
if (*format == '%')
{
format++;
switch (*format)
{
case '%':
break;
case 's':
{
const char* string = va_arg(arguments, const char*);
if (fputs(string, file) == EOF)
return -1;
written += strlen(string);
format++;
break;
}
default:
break;
}
}
if (fputc(*format, file) == EOF)
return -1;
written++;
format++;
}
return written;
}
// TODO
int vfscanf(FILE*, const char*, va_list);
int vprintf(const char* format, va_list arguments)
{
return vfprintf(stdout, format, arguments);
}
// TODO
int vscanf(const char*, va_list);
// TODO
int vsnprintf(char*, size_t, const char*, va_list);
// TODO
int vsprintf(char*, const char*, va_list);
// TODO
int vsscanf(const char*, const char*, va_list);