8.2: initial commit

4 files changed, 153 insertions, 0 deletions

diff --git a/8.2/Makefile b/8.2/Makefile
new file mode 100644
index 0000000..e77912f
--- /dev/null
+++ b/8.2/Makefile
@@ -0,0 +1,13 @@
+OBJECTS = main.o stdio.o
+CC = gcc
+CFLAGS = -Wvla -Wall -Wextra -Wstrict-prototypes -Wmissing-prototypes -fsanitize=address
+
+exe : $(OBJECTS)
+	$(CC) $(CFLAGS) -o exe $(OBJECTS)
+
+main.o : stdio.h
+
+.PHONY : clean
+
+clean :
+	rm -f exe $(OBJECTS)
diff --git a/8.2/main.c b/8.2/main.c
new file mode 100644
index 0000000..34d30a6
--- /dev/null
+++ b/8.2/main.c
@@ -0,0 +1,6 @@
+#include "stdio.h"
+
+int main(void)
+{
+	return 0;
+}
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++;
+}
diff --git a/8.2/stdio.h b/8.2/stdio.h
new file mode 100644
index 0000000..f7520de
--- /dev/null
+++ b/8.2/stdio.h
@@ -0,0 +1,48 @@
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#undef 	NULL
+#define NULL	0
+#define EOF	(-1)
+#define BUFSIZ	8192
+#define OPN_MAX	20
+
+struct flag_field {
+	unsigned int is_read	: 1;
+	unsigned int is_write	: 1;
+	unsigned int is_unbuf	: 1;
+	unsigned int is_buf	: 1;
+	unsigned int is_eof	: 1;
+	unsigned int is_err	: 1;
+};
+
+typedef struct _iobuff {
+	int cnt;
+	char *ptr;
+	char *base;
+	struct flag_field flag;
+	int fd;
+} FILE;
+
+extern FILE _iob[OPN_MAX];
+
+#define stdin	(&_iob[0]);
+#define stdout	(&_iob[1]);
+#define stderr	(&_iob[2]);
+
+int _fillbuf(FILE *);
+int _flushbuf(int, FILE *);
+FILE *fopen(char *name, char *mode);
+
+#define feof(p) (!!((p)->flag & _EOF))
+#define ferror(p) (!!((p)->flag & _ERR))
+#define fileno(p) ((p)->fd)
+
+#define getc(p)		(--(p)->cnt >= 0 \
+				? (unsigned char) *(p)->ptr++ : _fillbuf(p))
+#define putc(x, p)	(--(p)->cnt >= 0 \
+				? *(p)->ptr++ = x : _flushbuf(x, p))
+
+#define getchar()	getc(stdin)
+#define putchar(x)	putc(x, stdin)