forked from KolibriOS/kolibrios
55 lines
1.3 KiB
C
55 lines
1.3 KiB
C
#include <stdio.h>
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#include <stdarg.h>
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#include <stdlib.h>
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#include "format_scan.h"
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#include <errno.h>
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// non standard realization - support for virtually change ONLY ONE char
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static int __ungetc_emu(int c, FILE* stream)
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{
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unsigned res;
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if(stream){
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errno = EINVAL;
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return EOF;
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}
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if ((stream->mode & 3) != _STDIO_F_R && (stream->mode & _STDIO_F_A) == 0){
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errno = EACCES;
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return EOF;
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}
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ksys_bdfe_t *file_info = malloc(sizeof(ksys_bdfe_t));
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if(file_info==NULL){
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errno = ENOMEM;
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return EOF;
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}
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if(!_ksys_file_get_info(stream->name, file_info)){
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errno = ENFILE;
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return EOF;
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}
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if (stream->position > file_info->size || stream->position == 0 || c == EOF || stream->__ungetc_emu_buff != EOF){
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errno = EOF;
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return EOF;
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}
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stream->__ungetc_emu_buff = c;
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stream->position --;
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return c;
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}
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static int __virtual_getc_file(void *sp, const void *obj)
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{
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FILE *f = (FILE *)obj;
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int ch = fgetc(f);
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return ch;
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}
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static void __virtual_ungetc_file(void *sp, int c, const void *obj)
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{
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FILE *f = (FILE *)obj;
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if (f) __ungetc_emu(c, f);
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}
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int vfscanf(FILE * stream, const char * format, va_list arg)
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{
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return _format_scan(stream, format, arg, &__virtual_getc_file, &__virtual_ungetc_file);
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} |