toaruos/libc/stdio/stdio.c
2018-05-15 12:39:38 +09:00

342 lines
5.9 KiB
C

#include <stdio.h>
#include <syscall.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <_xlog.h>
struct _FILE {
int fd;
char * read_buf;
int available;
int offset;
int read_from;
int ungetc;
int eof;
};
FILE _stdin = {
.fd = 0,
.read_buf = NULL,
.available = 0,
.offset = 0,
.read_from = 0,
.ungetc = -1,
.eof = 0,
};
FILE _stdout = {
.fd = 1,
.read_buf = NULL,
.available = 0,
.offset = 0,
.read_from = 0,
.ungetc = -1,
.eof = 0,
};
FILE _stderr = {
.fd = 2,
.read_buf = NULL,
.available = 0,
.offset = 0,
.read_from = 0,
.ungetc = -1,
.eof = 0,
};
FILE * stdin = &_stdin;
FILE * stdout = &_stdout;
FILE * stderr = &_stderr;
void __stdio_init_buffers(void) {
_stdin.read_buf = malloc(BUFSIZ);
//_stdout.read_buf = malloc(BUFSIZ);
//_stderr.read_buf = malloc(BUFSIZ);
}
#if 0
static char * stream_id(FILE * stream) {
static char out[] = "stream\0\0\0\0\0\0";
if (stream == &_stdin) return "stdin";
if (stream == &_stdout) return "stdout";
if (stream == &_stderr) return "stderr";
sprintf(out, "stream %d", fileno(stream));
return out;
}
#endif
extern char * _argv_0;
static size_t read_bytes(FILE * f, char * out, size_t len) {
size_t r_out = 0;
//fprintf(stderr, "%s: Read %d bytes from %s\n", _argv_0, len, stream_id(f));
//fprintf(stderr, "%s: off[%d] avail[%d] read[%d]\n", _argv_0, f->offset, f->available, f->read_from);
while (len > 0) {
if (f->ungetc >= 0) {
*out = f->ungetc;
len--;
out++;
r_out++;
f->ungetc = -1;
continue;
}
if (f->available == 0) {
if (f->offset == BUFSIZ) {
f->offset = 0;
}
ssize_t r = read(fileno(f), &f->read_buf[f->offset], BUFSIZ - f->offset);
if (r < 0) {
//fprintf(stderr, "error condition\n");
return r_out;
} else {
f->read_from = f->offset;
f->available = r;
f->offset += f->available;
}
}
if (f->available == 0) {
/* EOF condition */
//fprintf(stderr, "%s: no bytes available, returning read value of %d\n", _argv_0, r_out);
f->eof = 1;
return r_out;
}
//fprintf(stderr, "%s: reading until %d reaches %d or %d reaches 0\n", _argv_0, f->read_from, f->offset, len);
while (f->read_from < f->offset && len > 0) {
*out = f->read_buf[f->read_from];
len--;
f->read_from++;
f->available--;
out++;
r_out += 1;
}
}
//fprintf(stderr, "%s: read completed, returning read value of %d\n", _argv_0, r_out);
return r_out;
}
FILE * fopen(const char *path, const char *mode) {
const char * x = mode;
int flags = 0;
int mask = 0;
while (*x) {
if (*x == 'a') {
flags |= O_WRONLY;
flags |= O_APPEND;
flags |= O_CREAT;
}
if (*x == 'w') {
flags |= O_WRONLY;
}
if (*x == '+') {
if (flags & O_WRONLY) {
flags |= O_CREAT;
mask = 0666;
} else {
flags |= O_WRONLY;
}
}
++x;
}
int fd = syscall_open(path, flags, mask);
if (fd < 0) {
return NULL;
}
FILE * out = malloc(sizeof(FILE));
out->fd = fd;
out->read_buf = malloc(BUFSIZ);
out->available = 0;
out->read_from = 0;
out->offset = 0;
out->ungetc = -1;
out->eof = 0;
return out;
}
int ungetc(int c, FILE * stream) {
if (stream->ungetc > 0)
return EOF;
return (stream->ungetc = c);
}
FILE * fdopen(int fd, const char *mode){
FILE * out = malloc(sizeof(FILE));
out->fd = fd;
out->read_buf = malloc(BUFSIZ);
out->available = 0;
out->read_from = 0;
out->offset = 0;
out->ungetc = -1;
out->eof = 0;
return out;
}
int _fwouldblock(FILE * stream) {
return !stream->available;
}
int fclose(FILE * stream) {
int out = syscall_close(stream->fd);
free(stream->read_buf);
if (stream == &_stdin || stream == &_stdout || stream == &_stderr) {
return out;
} else {
free(stream);
return out;
}
}
int fseek(FILE * stream, long offset, int whence) {
//fprintf(stderr, "%s: seek called, resetting\n", _argv_0);
stream->offset = 0;
stream->read_from = 0;
stream->available = 0;
stream->ungetc = -1;
stream->eof = 0;
int resp = syscall_lseek(stream->fd,offset,whence);
if (resp < 0) {
return -1;
}
return 0;
}
long ftell(FILE * stream) {
//fprintf(stderr, "%s: tell called, resetting\n", _argv_0);
stream->offset = 0;
stream->read_from = 0;
stream->available = 0;
stream->ungetc = -1;
stream->eof = 0;
return syscall_lseek(stream->fd, 0, SEEK_CUR);
}
size_t fread(void *ptr, size_t size, size_t nmemb, FILE * stream) {
char * tracking = (char*)ptr;
for (size_t i = 0; i < nmemb; ++i) {
int r = read_bytes(stream, tracking, size);
if (r < 0) {
return -1;
}
tracking += r;
if (r < (int)size) {
return i;
}
}
return nmemb;
}
size_t fwrite(const void *ptr, size_t size, size_t nmemb, FILE * stream) {
char * tracking = (char*)ptr;
for (size_t i = 0; i < nmemb; ++i) {
int r = syscall_write(stream->fd, tracking, size);
if (r < 0) {
_XLOG("write error in fwrite");
return -1;
}
tracking += r;
if (r < (int)size) {
return i;
}
}
return nmemb;
}
int fileno(FILE * stream) {
return stream->fd;
}
int fflush(FILE * stream) {
return 0;
}
int fputs(const char *s, FILE *stream) {
fwrite(s, strlen(s), 1, stream);
/* eof? */
return 0;
}
int fputc(int c, FILE *stream) {
char data[] = {c};
fwrite(data, 1, 1, stream);
return c;
}
int fgetc(FILE * stream) {
char buf[1];
int r;
r = fread(buf, 1, 1, stream);
if (r < 0) {
stream->eof = 1;
return EOF;
} else if (r == 0) {
stream->eof = 1;
return EOF;
}
return (unsigned char)buf[0];
}
char *fgets(char *s, int size, FILE *stream) {
int c;
char * out = s;
while ((c = fgetc(stream)) > 0) {
*s++ = c;
size--;
if (size == 0) {
return out;
}
*s = '\0';
if (c == '\n') {
return out;
}
}
if (c == EOF) {
stream->eof = 1;
if (out == s) {
return NULL;
} else {
return out;
}
}
return NULL;
}
int putchar(int c) {
return fputc(c, stdout);
}
void rewind(FILE *stream) {
fseek(stream, 0, SEEK_SET);
}
void setbuf(FILE * stream, char * buf) {
// ...
}
int feof(FILE * stream) {
return stream->eof;
}
void clearerr(FILE * stream) {
stream->eof = 0;
}