Import sources from 2011-03-30 iso image

1 files changed, 154 insertions, 0 deletions

diff --git a/sys/src/cmd/ip/httpd/save.c b/sys/src/cmd/ip/httpd/save.c
new file mode 100755
index 000000000..d80323ae1
--- /dev/null
+++ b/sys/src/cmd/ip/httpd/save.c
@@ -0,0 +1,154 @@
+/*
+ * for GET or POST to /magic/save/foo.
+ * add incoming data to foo.data.
+ * send foo.html as reply.
+ *
+ * supports foo.data with "exclusive use" mode to prevent interleaved saves.
+ * thus http://cm.bell-labs.com/magic/save/t?args should access:
+ * -lrw-rw--w- M 21470 ehg web 1533 May 21 18:19 /usr/web/save/t.data
+ * --rw-rw-r-- M 21470 ehg web   73 May 21 18:17 /usr/web/save/t.html
+*/
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include "httpd.h"
+#include "httpsrv.h"
+
+enum
+{
+	MaxLog		= 24*1024,		/* limit on length of any one log request */
+	LockSecs	= MaxLog/500,		/* seconds to wait before giving up on opening the data file */
+};
+
+static int
+dangerous(char *s)
+{
+	if(s == nil)
+		return 1;
+
+	/*
+	 * This check shouldn't be needed;
+	 * filename folding is already supposed to have happened.
+	 * But I'm paranoid.
+	 */
+	while(s = strchr(s,'/')){
+		if(s[1]=='.' && s[2]=='.')
+			return 1;
+		s++;
+	}
+	return 0;
+}
+
+/*
+ * open a file which might be locked.
+ * if it is, spin until available
+ */
+int
+openLocked(char *file, int mode)
+{
+	char buf[ERRMAX];
+	int tries, fd;
+
+	for(tries = 0; tries < LockSecs*2; tries++){
+		fd = open(file, mode);
+		if(fd >= 0)
+			return fd;
+		errstr(buf, sizeof buf);
+		if(strstr(buf, "locked") == nil)
+			break;
+		sleep(500);
+	}
+	return -1;
+}
+
+void
+main(int argc, char **argv)
+{
+	HConnect *c;
+	Dir *dir;
+	Hio *hin, *hout;
+	char *s, *t, *fn;
+	int n, nfn, datafd, htmlfd;
+
+	c = init(argc, argv);
+
+	if(dangerous(c->req.uri)){
+		hfail(c, HSyntax);
+		exits("failed");
+	}
+
+	if(hparseheaders(c, HSTIMEOUT) < 0)
+		exits("failed");
+	hout = &c->hout;
+	if(c->head.expectother){
+		hfail(c, HExpectFail, nil);
+		exits("failed");
+	}
+	if(c->head.expectcont){
+		hprint(hout, "100 Continue\r\n");
+		hprint(hout, "\r\n");
+		hflush(hout);
+	}
+
+	s = nil;
+	if(strcmp(c->req.meth, "POST") == 0){
+		hin = hbodypush(&c->hin, c->head.contlen, c->head.transenc);
+		if(hin != nil){
+			alarm(HSTIMEOUT);
+			s = hreadbuf(hin, hin->pos);
+			alarm(0);
+		}
+		if(s == nil){
+			hfail(c, HBadReq, nil);
+			exits("failed");
+		}
+		t = strchr(s, '\n');
+		if(t != nil)
+			*t = '\0';
+	}else if(strcmp(c->req.meth, "GET") != 0 && strcmp(c->req.meth, "HEAD") != 0){
+		hunallowed(c, "GET, HEAD, PUT");
+		exits("unallowed");
+	}else
+		s = c->req.search;
+	if(s == nil){
+		hfail(c, HNoData, "save");
+		exits("failed");
+	}
+
+	if(strlen(s) > MaxLog)
+		s[MaxLog] = '\0';
+	n = snprint(c->xferbuf, HBufSize, "at %ld %s\n", time(0), s);
+
+
+	nfn = strlen(c->req.uri) + 64;
+	fn = halloc(c, nfn);
+
+	/*
+	 * open file descriptors & write log line
+	 */
+	snprint(fn, nfn, "/usr/web/save/%s.html", c->req.uri);
+	htmlfd = open(fn, OREAD);
+	if(htmlfd < 0 || (dir = dirfstat(htmlfd)) == nil){
+		hfail(c, HNotFound, c->req.uri);
+		exits("failed");
+		return;
+	}
+
+	snprint(fn, nfn, "/usr/web/save/%s.data", c->req.uri);
+	datafd = openLocked(fn, OWRITE);
+	if(datafd < 0){
+		errstr(c->xferbuf, sizeof c->xferbuf);
+		if(strstr(c->xferbuf, "locked") != nil)
+			hfail(c, HTempFail, c->req.uri);
+		else
+			hfail(c, HNotFound, c->req.uri);
+		exits("failed");
+	}
+	seek(datafd, 0, 2);
+	write(datafd, c->xferbuf, n);
+	close(datafd);
+
+	sendfd(c, htmlfd, dir, hmkcontent(c, "text", "html", nil), nil);
+
+	exits(nil);
+}