44 lines
652 B
C
44 lines
652 B
C
/*
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* fopen.c
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*/
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#include <stdio.h>
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#include <unistd.h>
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#include <fcntl.h>
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FILE *fopen(const char *file, const char *mode)
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{
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int flags = O_RDONLY;
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int plus = 0;
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int fd;
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while ( *mode ) {
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switch ( *mode ) {
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case 'r':
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flags = O_RDONLY;
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break;
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case 'w':
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flags = O_WRONLY|O_CREAT|O_TRUNC;
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break;
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case 'a':
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flags = O_WRONLY|O_CREAT|O_APPEND;
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break;
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case '+':
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plus = 1;
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break;
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}
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mode++;
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}
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if ( plus ) {
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flags = (flags & ~(O_RDONLY|O_WRONLY)) | O_RDWR;
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}
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fd = open(file, flags, 0666);
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if ( fd < 0 )
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return NULL;
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else
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return fdopen(fd, mode);
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}
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