qcqmifs: initial version

Signed-off-by: Bjørn Mork <bjorn@mork.no>

2 files changed, 270 insertions, 1 deletions

diff --git a/src/Makefile b/src/Makefile
index 4443538..9d66584 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,4 +1,13 @@
-all: wwan_ctl qmi-prober
+CC=gcc
+CFLAGS_FUSE=$(shell pkg-config fuse --cflags)
+LDLIBS_FUSE=$(shell pkg-config fuse --libs)
+LDFLAGS=-Wall
+BINARIES=wwan_ctl qcqmifs
+
+all: $(BINARIES)
+
+clean:
+	rm -rf *.o *.so *.lo *~ $(BINARIES) .libs
 
 wwan_ctl: wwan_ctl.c
 	gcc -o wwan_ctl wwan_ctl.c
@@ -6,3 +15,6 @@ wwan_ctl: wwan_ctl.c
 qmi-prober: qmi-prober.c
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LDLIBS)
 
+qcqmifs: qcqmifs.c
+	$(CC) $(CFLAGS) $(CFLAGS_FUSE) $(LDFLAGS) -o $@ $^ $(LDLIBS) $(LDLIBS_FUSE)
+
diff --git a/src/qcqmifs.c b/src/qcqmifs.c
new file mode 100644
index 0000000..c29988f
--- /dev/null
+++ b/src/qcqmifs.c
@@ -0,0 +1,257 @@
+/*
+  qcqmifs - an example of how to use FUSE to create a shim between the
+  proprietary Qualcomm QMI SDK and the qmi_wwan driver in the mainline
+  Linux kernel.
+  
+  This code is heavily based on the FUSE "hello" example, which is
+
+    Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
+
+  The Qualcomm QMI SDK interface expectations are pulled from the nicely
+  rewritten Qualcomm Gobi 2000/3000 driver by Elly Jones <ellyjones@google.com>.
+  That driver is 
+
+    Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+
+  The rest of the glue is
+
+    Copyright (C) 2012 Bjørn Mork <bjorn@mork.no>
+
+  This program can be distributed under the terms of the GNU GPLv2.
+  See the file COPYING.
+
+  
+  Building it:
+  gcc -Wall `pkg-config fuse --cflags --libs` qcqmifs.c -o qcqmifs
+
+  Running it (with the optional:
+  # ./qcqmifs /mnt/whatever -d -o default_permissions,allow_other
+
+  Using it:
+
+  - all existing /dev/cdc-wdmX devices will get a mirror 
+     device under the chosen mountpoint named /mnt/whatever/qcqmiX
+
+  - create a symlink from /dev/qcqmi or /dev/qcqmi0 to the wanted
+     mirror device
+
+ Restrictions:
+
+   - no dynamic device discovery.  Program must be restarted to detect
+     new or removed devices
+
+   - no automatic symlinking
+
+   - /dev/qcqmiX where X > 0 is not supported by the SDK, so the symlink
+     names cannot always match real device names
+
+
+*/
+
+/* FUSE API version */
+#define FUSE_USE_VERSION 26
+
+#include <fuse.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <dirent.h>
+
+static int qcqmi_getattr(const char *path, struct stat *stbuf)
+{
+	int res = 0;
+	int x;
+	char name[] = "/dev/cdc-wdmX";
+
+	fprintf(stderr, "%s: path=%s\n", __func__, path);
+
+	if (strcmp(path, "/") == 0) {
+		memset(stbuf, 0, sizeof(struct stat));
+		stbuf->st_mode = S_IFDIR | 0755;
+		stbuf->st_nlink = 2;
+	} else {
+		if (strncmp("/qcqmi", path, 6))
+			return -EINVAL;
+
+		x = strtoul(path + 6, NULL, 10);
+		if (x > 9)
+			return -EINVAL;
+
+		sprintf(name, "/dev/cdc-wdm%u", x);
+		res = stat(name, stbuf);
+		stbuf->st_mode = S_IFREG | 0664;
+	}
+
+	return res;
+}
+
+static int cdcwdm_filter(const struct dirent *d)
+{
+	return !strncmp("cdc-wdm", d->d_name, 7);
+}
+
+
+/* create a directory mirror of the current /dev/cdc-wdmX devices */
+static int qcqmi_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
+			 off_t offset, struct fuse_file_info *fi)
+{
+	(void) offset;
+	(void) fi;
+	struct dirent **namelist;
+	int i, n, x;
+	char name[6];
+
+	if (strcmp(path, "/") != 0)
+		return -ENOENT;
+
+	fprintf(stderr, "%s: path=%s\n", __func__, path);
+
+	filler(buf, ".", NULL, 0);
+	filler(buf, "..", NULL, 0);
+	
+	n = scandir("/dev", &namelist, cdcwdm_filter, alphasort);
+	if (n < 0)
+		return n;
+
+	for (i = 0; i < n; i++) {
+		x =  strtoul(namelist[i]->d_name + 7, NULL, 10);
+		if (x < 10) {
+			sprintf(name, "qcqmi%u", x);
+			filler(buf, name, NULL, 0);
+		}
+		free(namelist[i]);
+	}
+	free(namelist);
+	return 0;
+}
+
+struct cdcwdmdev {
+	char *name;
+	int fd;
+	int cid;
+};
+
+static int qcqmi_open(const char *path, struct fuse_file_info *fi)
+{
+	int fd, x;
+	char name[] = "/dev/cdc-wdmX";
+	struct cdcwdmdev *handle;
+
+	fprintf(stderr, "%s: path=%s\n", __func__, path);
+
+	if (strncmp("/qcqmi", path, 6))
+		return -EINVAL;
+
+	x = strtoul(path + 6, NULL, 10);
+	if (x > 9)
+		return -EINVAL;
+	sprintf(name, "/dev/cdc-wdm%u", x);
+
+	fd = open(name, fi->flags);
+	if (fd < 0) {
+		fprintf(stderr, "%s: open(%s) returned %d, errno=%d\n", __func__, name, fd, errno);
+		return -errno;
+	}
+
+	handle = malloc(sizeof(struct cdcwdmdev));
+	handle->name = strdup(name);
+	handle->fd = fd;
+	handle->cid = -1; /* invalid */
+
+	fi->nonseekable = 1;
+	fi->fh = (uint64_t)handle;
+
+	return 0;
+}
+
+static int qcqmi_release(const char *path, struct fuse_file_info *fi)
+{
+	struct cdcwdmdev *handle = (void *)fi->fh;
+
+	fprintf(stderr, "%s: path=%s\n", __func__, path);
+
+	fi->fh = (uint64_t)NULL;
+	close(handle->fd);
+	free(handle->name);
+	free(handle);
+	return 0;
+}
+
+
+static int qcqmi_read(const char *path, char *buf, size_t size, off_t offset,
+		      struct fuse_file_info *fi)
+{
+	struct cdcwdmdev *handle = (void *)fi->fh;
+
+	fprintf(stderr, "%s: path=%s, proxying to %s\n", __func__, path, handle->name);
+	return 0;
+}
+
+static int qcqmi_write(const char *path, const char *buf, size_t size, off_t offset,
+ 		       struct fuse_file_info *fi)
+{
+	struct cdcwdmdev *handle = (void *)fi->fh;
+
+	fprintf(stderr, "%s: path=%s, proxying to %s\n", __func__, path, handle->name);
+	
+	return size;
+}
+
+static int qcqmi_ioctl(const char *path, int cmd, void *arg,
+		       struct fuse_file_info *fi, unsigned int flags, void *data)
+{
+	struct cdcwdmdev *handle = (void *)fi->fh;
+
+	fprintf(stderr, "%s: path=%s, proxying to %s\n", __func__, path, handle->name);
+	return  -EBADRQC;
+}
+
+static int qcqmi_chmod(const char *path, mode_t mode)
+{
+	fprintf(stderr, "%s: path=%s, mode=%x\n", __func__, path, mode);
+	return 0;
+}
+
+
+static int qcqmi_chown(const char *path, uid_t uid, gid_t gid)
+{
+	fprintf(stderr, "%s: path=%s, uid=%u, gid=%u\n", __func__, path, uid, gid);
+	return 0;
+}
+
+static int qcqmi_utimens(const char *path, const struct timespec tv[2])
+{
+	fprintf(stderr, "%s: path=%s, tv[0].tv_sec=%lu, tv[1].tv_sec=%lu\n", __func__, path, tv[0].tv_sec, tv[1].tv_sec);
+	return 0;
+}
+
+/* must implement truncate to be able to write to an arbitrary offset */
+static int qcqmi_truncate(const char *path, off_t offset)
+{
+	fprintf(stderr, "%s: path=%s, offset=%lx\n", __func__, path, offset);
+	return 0;
+}
+
+static struct fuse_operations qcqmi_oper = {
+	.getattr	= qcqmi_getattr,
+	.readdir	= qcqmi_readdir,
+	.open		= qcqmi_open,
+	.release        = qcqmi_release,
+	.read		= qcqmi_read,
+	.write          = qcqmi_write,
+	.ioctl          = qcqmi_ioctl,
+//	.chown          = qcqmi_chown,
+//	.chmod          = qcqmi_chmod,
+//	.utimens        = qcqmi_utimens,
+	.truncate       = qcqmi_truncate,
+};
+
+int main(int argc, char *argv[])
+{
+	/* run file system */
+	return fuse_main(argc, argv, &qcqmi_oper, NULL);
+}