From 980d0a881f9309ef43881634ef1b1a6143b03ed7 Mon Sep 17 00:00:00 2001
From: Ron Economos <w6rz@comcast.net>
Date: Fri, 29 Mar 2019 17:05:02 -0700
Subject: blocks: Modify File Source block to work with named pipes and
devices.
The block uses fseek and ftell, which don't apply to named pipes
and character/block devices.
---
gr-blocks/lib/file_source_impl.cc | 98 ++++++++++++++++++++++++++-------------
1 file changed, 65 insertions(+), 33 deletions(-)
(limited to 'gr-blocks/lib/file_source_impl.cc')
diff --git a/gr-blocks/lib/file_source_impl.cc b/gr-blocks/lib/file_source_impl.cc
index 3f7b844e03..18bbc73be3 100644
--- a/gr-blocks/lib/file_source_impl.cc
+++ b/gr-blocks/lib/file_source_impl.cc
@@ -37,9 +37,13 @@
#ifdef _MSC_VER
#define GR_FSEEK _fseeki64
#define GR_FTELL _ftelli64
+#define GR_FSTAT _fstat
+#define GR_FILENO _fileno
#else
#define GR_FSEEK fseeko
#define GR_FTELL ftello
+#define GR_FSTAT fstat
+#define GR_FILENO fileno
#endif
namespace gr {
@@ -81,28 +85,34 @@ namespace gr {
bool
file_source_impl::seek(int64_t seek_point, int whence)
{
- seek_point += d_start_offset_items;
-
- switch(whence) {
- case SEEK_SET:
- break;
- case SEEK_CUR:
- seek_point += (d_length_items - d_items_remaining);
- break;
- case SEEK_END:
- seek_point = d_length_items - seek_point;
- break;
- default:
- GR_LOG_WARN(d_logger, "bad seek mode");
- return 0;
- }
+ if (d_seekable) {
+ seek_point += d_start_offset_items;
+
+ switch(whence) {
+ case SEEK_SET:
+ break;
+ case SEEK_CUR:
+ seek_point += (d_length_items - d_items_remaining);
+ break;
+ case SEEK_END:
+ seek_point = d_length_items - seek_point;
+ break;
+ default:
+ GR_LOG_WARN(d_logger, "bad seek mode");
+ return 0;
+ }
- if ((seek_point < (int64_t)d_start_offset_items)
- || (seek_point > (int64_t)(d_start_offset_items+d_length_items-1))) {
- GR_LOG_WARN(d_logger, "bad seek point");
+ if ((seek_point < (int64_t)d_start_offset_items)
+ || (seek_point > (int64_t)(d_start_offset_items+d_length_items-1))) {
+ GR_LOG_WARN(d_logger, "bad seek point");
+ return 0;
+ }
+ return GR_FSEEK((FILE*)d_fp, seek_point * d_itemsize, SEEK_SET) == 0;
+ }
+ else {
+ GR_LOG_WARN(d_logger, "file not seekable");
return 0;
}
- return GR_FSEEK((FILE*)d_fp, seek_point * d_itemsize, SEEK_SET) == 0;
}
@@ -123,20 +133,40 @@ namespace gr {
throw std::runtime_error("can't open file");
}
- //Check to ensure the file will be consumed according to item size
- GR_FSEEK(d_new_fp, 0, SEEK_END);
- uint64_t file_size = GR_FTELL(d_new_fp);
+ struct stat st;
- // Make sure there will be at least one item available
- if ((file_size / d_itemsize) < (start_offset_items+1)) {
- if (start_offset_items) {
- GR_LOG_WARN(d_logger, "file is too small for start offset");
- }
- else {
- GR_LOG_WARN(d_logger, "file is too small");
+ if(GR_FSTAT(GR_FILENO(d_new_fp), &st)) {
+ GR_LOG_ERROR(d_logger, boost::format("%s: %s") % filename % strerror(errno));
+ throw std::runtime_error("can't fstat file");
+ }
+ if(S_ISREG(st.st_mode)) {
+ d_seekable = true;
+ }
+ else {
+ d_seekable = false;
+ }
+
+ uint64_t file_size;
+
+ if (d_seekable) {
+ //Check to ensure the file will be consumed according to item size
+ GR_FSEEK(d_new_fp, 0, SEEK_END);
+ file_size = GR_FTELL(d_new_fp);
+
+ // Make sure there will be at least one item available
+ if ((file_size / d_itemsize) < (start_offset_items+1)) {
+ if (start_offset_items) {
+ GR_LOG_WARN(d_logger, "file is too small for start offset");
+ }
+ else {
+ GR_LOG_WARN(d_logger, "file is too small");
+ }
+ fclose(d_new_fp);
+ throw std::runtime_error("file is too small");
}
- fclose(d_new_fp);
- throw std::runtime_error("file is too small");
+ }
+ else {
+ file_size = INT64_MAX;
}
uint64_t items_available = (file_size / d_itemsize - start_offset_items);
@@ -156,7 +186,9 @@ namespace gr {
}
// Rewind to start offset
- GR_FSEEK(d_new_fp, start_offset_items * d_itemsize, SEEK_SET);
+ if (d_seekable) {
+ GR_FSEEK(d_new_fp, start_offset_items * d_itemsize, SEEK_SET);
+ }
d_updated = true;
d_repeat = repeat;
@@ -241,7 +273,7 @@ namespace gr {
if (d_items_remaining == 0) {
// Repeat: rewind and request tag
- if (d_repeat) {
+ if (d_repeat && d_seekable) {
GR_FSEEK(d_fp, d_start_offset_items * d_itemsize, SEEK_SET);
d_items_remaining = d_length_items;
if (d_add_begin_tag != pmt::PMT_NIL) {
--
cgit v1.2.3