Import sources from 2011-03-30 iso image

1 files changed, 56 insertions, 0 deletions

diff --git a/sys/src/libstdio/freopen.c b/sys/src/libstdio/freopen.c
new file mode 100755
index 000000000..a5ac25993
--- /dev/null
+++ b/sys/src/libstdio/freopen.c
@@ -0,0 +1,56 @@
+/*
+ * pANS stdio -- freopen
+ */
+#include "iolib.h"
+/*
+ * Open the named file with the given mode, using the given FILE
+ * Legal modes are given below, `additional characters may follow these sequences':
+ * r rb		open to read
+ * w wb		open to write, truncating
+ * a ab		open to write positioned at eof, creating if non-existant
+ * r+ r+b rb+	open to read and write, creating if non-existant
+ * w+ w+b wb+	open to read and write, truncating
+ * a+ a+b ab+	open to read and write, positioned at eof, creating if non-existant.
+ */
+FILE *freopen(const char *name, const char *mode, FILE *f){
+	int m;
+
+	if(f->state!=CLOSED){
+		fclose(f);
+/* premature; fall through and see what happens */
+/*		f->state=OPEN; */
+	}
+
+	m = *mode++;
+	if(m == 0)
+		return NULL;
+	if(*mode == 'b')
+		mode++;
+	switch(m){
+	default:
+		return NULL;
+	case 'r':
+		f->fd=open(name, (*mode == '+'? ORDWR: OREAD));
+		break;
+	case 'w':
+		f->fd=create(name, (*mode == '+'? ORDWR: OWRITE), 0666);
+		break;
+	case 'a':
+		m = (*mode == '+'? ORDWR: OWRITE);
+		f->fd=open(name, m);
+		if(f->fd<0)
+			f->fd=create(name, m, 0666);
+		seek(f->fd, 0LL, 2);
+		break;
+	}
+
+	if(f->fd==-1)
+		return NULL;
+	f->flags=(mode[0]=='a')? APPEND : 0;
+	f->state=OPEN;
+	f->buf=0;
+	f->rp=0;
+	f->wp=0;
+	f->lp=0;
+	return f;
+}