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-rw-r--r--8.3/stdio.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/8.3/stdio.c b/8.3/stdio.c
new file mode 100644
index 0000000..747a0ae
--- /dev/null
+++ b/8.3/stdio.c
@@ -0,0 +1,140 @@
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "stdio.h"
+
+#define PERMS 0666
+
+FILE _iob[OPN_MAX] = {
+ {0, NULL, NULL, _READ, 0},
+ {0, NULL, NULL, _WRITE, 1},
+ {0, NULL, NULL, _WRITE | _UNBUF, 2}
+};
+
+FILE *fopen(char *name, char *mode)
+{
+ FILE *fp;
+
+ if (*mode != 'r' && *mode != 'w' && *mode != 'a')
+ return NULL;
+
+ for(fp = _iob; fp < _iob + OPN_MAX; ++fp)
+ if (!(fp->flag & (_READ | _WRITE)))
+ break;
+ if (fp == _iob + OPN_MAX)
+ return NULL;
+
+ if (*mode == 'w') {
+ fp->fd = open(name, O_WRONLY);
+ } else if (*mode == 'a') {
+ if ((fp->fd = open(name, O_WRONLY)) == -1)
+ fp->fd = creat(name, PERMS);
+ lseek(fp->fd, 0L, 2);
+ } else {
+ fp->fd = open(name, O_RDONLY);
+ }
+
+ if (fp->fd == -1) {
+ fp->fd = 0;
+ return NULL;
+ }
+
+ fp->base = fp->ptr = NULL;
+ fp->flag = (*mode == 'r') ? _READ : _WRITE;
+ fp->cnt = 0;
+
+ return fp;
+}
+
+int _fillbuf(FILE *fp)
+{
+ int bufsize;
+
+ if ((fp->flag & (_READ | _EOF | _ERR)) != _READ)
+ return EOF;
+
+ bufsize = (fp->flag & _UNBUF) ? 1 : BUFSIZ;
+ if (fp->base == NULL)
+ if ((fp->base = 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 = _EOF;
+ else // fp->cnt == -2
+ fp->flag = _ERR;
+ fp->cnt = 0;
+ return EOF;
+ }
+
+ return (unsigned char) *fp->ptr++;
+}
+
+int _flushbuf(int c, FILE *fp)
+{
+ int bufsize, nc;
+
+ if ((fp->flag & (_WRITE | _ERR)) != _WRITE)
+ return EOF;
+
+ bufsize = (fp->flag & _UNBUF) ? 1 : BUFSIZ;
+ if (fp->base == NULL) {
+ if ((fp->base = malloc(bufsize)) == NULL)
+ return EOF;
+ } else {
+ nc = fp->ptr - fp->base;
+ if (write(fp->fd, fp->base, nc) != nc) {
+ fp->flag = _ERR;
+ return EOF;
+ }
+ }
+
+ fp->ptr = fp->base;
+ fp->cnt = bufsize - 1;
+ *fp->ptr++ = c;
+
+ return (unsigned char) c;
+}
+
+int fflush(FILE *fp)
+{
+ int rc = 0;
+
+ if (fp < _iob && fp >= _iob + OPN_MAX)
+ return EOF;
+ if (fp->flag & _WRITE)
+ rc = _flushbuf(0, fp);
+
+ fp->ptr = fp->base;
+ fp->cnt = (fp->flag & _UNBUF) ? 1 : BUFSIZ;
+
+ return rc;
+}
+
+
+int fclose(FILE *fp)
+{
+ int rc;
+
+ if ((rc = fflush(fp)) != EOF) {
+ free(fp->base);
+ fp->base = fp->ptr = NULL;
+ fp->flag &= ~(_READ | _WRITE);
+ fp->cnt = 0;
+ close(fp->fd);
+ }
+
+ return rc;
+}
+
+int puts(const char *s)
+{
+ while (*s)
+ if (putchar(*s++) == EOF)
+ return EOF;
+ fflush(stdout);
+
+ return 1;
+}