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-rw-r--r--8.2/stdio.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/8.2/stdio.c b/8.2/stdio.c
new file mode 100644
index 0000000..dd6cbef
--- /dev/null
+++ b/8.2/stdio.c
@@ -0,0 +1,86 @@
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include "stdio.h"
+
+#define PERMS 0666
+
+FILE _iob[OPN_MAX] = {
+ {0, (char *) NULL, (char *) NULL, {1, 0, 0, 1, 0, 0}, 0},
+ {0, (char *) NULL, (char *) NULL, {0, 1, 0, 1, 0, 0}, 1},
+ {0, (char *) NULL, (char *) NULL, {0, 1, 1, 0, 0, 0}, 2},
+};
+
+FILE *fopen(char *name, char *mode)
+{
+ int fd;
+ FILE *fp;
+
+ if (*mode != 'r' && *mode != 'w' && *mode != 'a')
+ return NULL;
+
+ for (fp = _iob; fp < _iob + OPN_MAX; ++fp)
+ if (fp->flag.is_read == 0 && fp->flag.is_write == 0)
+ break;
+ if (fp == _iob + OPN_MAX)
+ return NULL;
+
+ if (*mode == 'w') {
+ fd = creat(name, PERMS);
+ } else if (*mode == 'a') {
+ if ((fd = open(name, O_WRONLY)) == -1)
+ fd = creat(name, PERMS);
+ lseek(fd, 0L, 2);
+ } else {
+ fd = open(name, O_RDONLY);
+ }
+
+ if (fd == -1)
+ return NULL;
+
+ fp->fd = fd;
+ fp->cnt = 0;
+ fp->base = NULL;
+ fp->flag.is_unbuf = 0;
+ fp->flag.is_buf = 1;
+ fp->flag.is_eof = 0;
+ fp->flag.is_err = 0;
+ if (*mode == 'r') {
+ fp->flag.is_read = 1;
+ fp->flag.is_write = 0;
+ } else {
+ fp->flag.is_write = 1;
+ fp->flag.is_read = 0;
+ }
+
+ return fp;
+}
+
+int _fillbuf(FILE *fp)
+{
+ int bufsize;
+
+ if (fp->flag.is_read == 0 ||
+ fp->flag.is_err == 1 ||
+ fp->flag.is_eof == 1)
+ return EOF;
+
+ bufsize = (fp->flag.is_unbuf == 1) ? 1 : BUFSIZ;
+ if (fp->base == NULL)
+ if ((fp->base = (char *) malloc(bufsize)) == NULL)
+ return EOF;
+ fp->ptr = fp->base;
+
+ fp->cnt = read(fp->fd, fp->base, bufsize);
+ if (--fp->cnt < 0) {
+ if (fp->cnt == -1)
+ fp->flag.is_eof = 1;
+ else
+ fp->flag.is_err = 1;
+ fp->cnt = 0;
+ return EOF;
+ }
+
+ return (unsigned char) *fp->ptr++;
+}