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| #include "minicrt.h"
int CrtInitIo()
{
return 0;
}
static int open(const char *pathname, int flags, int mode)
{
int ret;
__asm__ volatile(
"int $0x80"
:"=a"(ret)
:"0"(5),"b"(pathname),"c"(flags),"d"(mode)
);
if (ret >= 0)
return ret;
return -1;
}
static int write(int fd, const void *buf, int count)
{
int ret;
__asm__ volatile(
"int $0x80"
:"=a"(ret)
:"0"(4),"b"(fd),"c"(buf),"d"(count)
);
if (ret >= 0)
return ret;
return -1;
}
static int read(int fd, void *buf, int count)
{
int ret;
__asm__ volatile(
"int $0x80"
:"=a"(ret)
:"0"(3),"b"(fd),"c"(buf),"d"(count)
);
if (ret >= 0)
return ret;
return -1;
}
static int close(int fd)
{
int ret;
__asm__ volatile(
"int $0x80"
:"=a"(ret)
:"0"(6),"b"(fd)
);
if (ret >= 0)
return ret;
return -1;
}
int lseek(int fd, int offset, int whence)
{
int ret;
__asm__ volatile(
"int $0x80"
:"=a"(ret)
:"0"(19),"b"(fd),"c"(offset),"d"(whence)
);
if (ret >= 0)
return ret;
return -1;
}
int fread(void *ptr, int size, int nmemb, FILE *stream)
{
return read((int)stream, ptr, size * nmemb);
}
int fwrite(const void *ptr, int size, int nmemb, FILE *stream)
{
return write((int)stream, ptr, size * nmemb);
}
FILE *fopen(const char *path, const char *mode)
{
int fd = -1;
int flags = 0;
int access = 00700;
if (strcmp(mode, "w") == 0)
flags |= O_WRONLY | O_CREAT | O_TRUNC;
if (strcmp(mode, "w+") == 0)
flags |= O_RDWR | O_CREAT | O_TRUNC;
if (strcmp(mode, "r") == 0)
flags |= O_RDONLY;
if (strcmp(mode, "r+") == 0)
flags |= O_RDWR | O_CREAT;
fd = open(path, flags, access);
return (FILE *)fd;
}
int fclose(FILE *fp)
{
return close((int)fp);
}
int fseek(FILE *stream, long offset, int whence)
{
return lseek((int)stream, offset, whence);
}
int fputc(int c, FILE *stream)
{
if (fwrite(&c, 1, 1, stream) != 1)
return EOF;
else
return c;
}
int fputs(const char *s, FILE *stream)
{
int len;
len = strlen(s);
if (fwrite(s, 1, len, stream) != len)
return EOF;
else
return len;
}
int vfprintf(FILE *stream, const char *format, va_list ap)
{
int n = 0, flag = 0, ret;
char str[20];
while (*format)
{
switch (*format)
{
case '%':
if (flag == 1)
{
fputc('%', stream);
flag = 0;
n ++;
}
else
flag = 1;
break;
case 'd':
if (flag == 1)
{
itoa((int)va_arg(ap, int), str, 10);
ret = fputs(str, stream);
n += ret;
}
else
{
fputc('d', stream);
n ++;
}
flag = 0;
break;
case 's':
if (flag == 1)
{
ret = fputs((char *)va_arg(ap, char *), stream);
n += ret;
}
else
{
fputc('s', stream);
n ++;
}
flag = 0;
break;
case '\n':
fputc(0x0d, stream);
n ++;
fputc(0x0a, stream);
n ++;
break;
default:
fputc(*format, stream);
n ++;
}
format ++;
}
return n;
}
int fprintf(FILE *stream, const char *format, ...)
{
int n;
va_list ap;
va_start(ap, format);
n = vfprintf(stream, format, ap);
va_end(ap);
return n;
}
int printf(const char *format, ...)
{
int n;
va_list ap;
va_start(ap, format);
n = vfprintf(stdout, format, ap);
va_end(ap);
return n;
}
|
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