Import sources from 2011-03-30 iso image

1 files changed, 257 insertions, 0 deletions

diff --git a/sys/src/cmd/ip/ftpfs/file.c b/sys/src/cmd/ip/ftpfs/file.c
new file mode 100755
index 000000000..ff5bfeca0
--- /dev/null
+++ b/sys/src/cmd/ip/ftpfs/file.c
@@ -0,0 +1,257 @@
+#include <u.h>
+#include <libc.h>
+#include <String.h>
+#include "ftpfs.h"
+
+enum
+{
+	Chunk=		1024,		/* chunk size for buffered data */
+	Nfile=		128,		/* maximum number of cached files */
+};
+
+/* a file (with cached data) */
+struct File
+{
+	char	*mem;		/* part of file cached in memory */
+	ulong	len;		/* length of cached data */
+	long	off;		/* current offset into tpath */
+	short	fd;		/* fd to cache file */
+	char	inuse;
+	char	dirty;
+	ulong	atime;		/* time of last access */
+	Node	*node;
+	char 	*template;
+};
+
+static File	files[Nfile];
+static ulong	now;
+static int	ntmp;
+
+/*
+ *  lookup a file, create one if not found.  if there are no
+ *  free files, free the last oldest clean one.
+ */
+static File*
+fileget(Node *node)
+{
+	File *fp;
+	File *oldest;
+
+	fp = node->fp;
+	if(fp)
+		return fp;
+
+	oldest = 0;
+	for(fp = files; fp < &files[Nfile]; fp++){
+		if(fp->inuse == 0)
+			break;
+		if(fp->dirty == 0 && (oldest == 0 || oldest->atime > fp->atime))
+			oldest = fp;
+	}
+
+	if(fp == &files[Nfile]){
+		uncache(oldest->node);
+		fp = oldest;
+	}
+	node->fp = fp;
+	fp->node = node;
+	fp->atime = now++;
+	fp->inuse = 1;
+	fp->fd = -1;
+	if(fp->mem){
+		free(fp->mem);
+		fp->mem = nil;
+	}
+	return fp;
+}
+
+/*
+ *  free a cached file
+ */
+void
+filefree(Node *node)
+{
+	File *fp;
+
+	fp = node->fp;
+	if(fp == 0)
+		return;
+
+	if(fp->fd > 0){
+		ntmp--;
+		close(fp->fd);
+		remove(fp->template);
+		free(fp->template);
+		fp->template = 0;
+	}
+	fp->fd = -1;
+	if(fp->mem){
+		free(fp->mem);
+		fp->mem = nil;
+	}
+	fp->len = 0;
+	fp->inuse = 0;
+	fp->dirty = 0;
+
+	node->fp = 0;
+}
+
+/*
+ *  satisfy read first from in memory chunk and then from temporary
+ *  file.  It's up to the caller to make sure that the file is valid.
+ */
+int
+fileread(Node *node, char *a, long off, int n)
+{
+	int sofar;
+	int i;
+	File *fp;
+
+	fp = node->fp;
+	if(fp == 0)
+		fatal("fileread");
+
+	if(off + n > fp->len)
+		n = fp->len - off;
+
+	for(sofar = 0; sofar < n; sofar += i, off += i, a += i){
+		if(off >= fp->len)
+			return sofar;
+		if(off < Chunk){
+			i = n;
+			if(off + i > Chunk)
+				i = Chunk - off;
+			memmove(a, fp->mem + off, i);
+			continue;
+		}
+		if(fp->off != off)
+			if(seek(fp->fd, off, 0) < 0){
+				fp->off = -1;
+				return -1;
+			}
+		i = read(fp->fd, a, n-sofar);
+		if(i < 0){
+			fp->off = -1;
+			return -1;
+		}
+		if(i == 0)
+			break;
+		fp->off = off + i;
+	}
+	return sofar;
+}
+
+void
+uncachedir(Node *parent, Node *child)
+{
+	Node *sp;
+
+	if(parent == 0 || parent == child)
+		return;
+	for(sp = parent->children; sp; sp = sp->sibs)
+		if(sp->opens == 0)
+		if(sp != child)
+		if(sp->fp != nil)
+		if(sp->fp->dirty == 0)
+		if(sp->fp->fd >= 0){
+			filefree(sp);
+			UNCACHED(sp);
+		}
+}
+
+static int
+createtmp(File *fp)
+{
+	char template[32];
+
+	strcpy(template, "/tmp/ftpXXXXXXXXXXX");
+	mktemp(template);
+	if(strcmp(template, "/") == 0){
+		fprint(2, "ftpfs can't create tmp file %s: %r\n", template);
+		return -1;
+	}
+	if(ntmp >= 16)
+		uncachedir(fp->node->parent, fp->node);
+
+	fp->fd = create(template, ORDWR|ORCLOSE, 0600);
+	fp->template = strdup(template);
+	fp->off = 0;
+	ntmp++;
+	return fp->fd;
+}
+
+/*
+ *  write cached data (first Chunk bytes stay in memory)
+ */
+int
+filewrite(Node *node, char *a, long off, int n)
+{
+	int i, sofar;
+	File *fp;
+
+	fp = fileget(node);
+
+	if(fp->mem == nil){
+		fp->mem = malloc(Chunk);
+		if(fp->mem == nil)
+			return seterr("out of memory");
+	}
+
+	for(sofar = 0; sofar < n; sofar += i, off += i, a += i){
+		if(off < Chunk){
+			i = n;
+			if(off + i > Chunk)
+				i = Chunk - off;
+			memmove(fp->mem + off, a, i);
+			continue;
+		}
+		if(fp->fd < 0)
+			if(createtmp(fp) < 0)
+				return seterr("can't create temp file");
+		if(fp->off != off)
+			if(seek(fp->fd, off, 0) < 0){
+				fp->off = -1;
+				return seterr("can't seek temp file");
+			}
+		i = write(fp->fd, a, n-sofar);
+		if(i <= 0){
+			fp->off = -1;
+			return seterr("can't write temp file");
+		}
+		fp->off = off + i;
+	}
+
+	if(off > fp->len)
+		fp->len = off;
+	if(off > node->d->length)
+		node->d->length = off;
+	return sofar;
+}
+
+/*
+ *  mark a file as dirty
+ */
+void
+filedirty(Node *node)
+{
+	File *fp;
+
+	fp = fileget(node);
+	fp->dirty = 1;
+}
+
+/*
+ *  mark a file as clean
+ */
+void
+fileclean(Node *node)
+{
+	if(node->fp)
+		node->fp->dirty = 0;
+}
+
+int
+fileisdirty(Node *node)
+{
+	return node->fp && node->fp->dirty;
+}