output to stdout if file name is "-"
Doesn't work with WIC
+ redirect some info messages from stdout to stderr
+ fix the error reporting upon output-writing error
Change-Id: I92b8bd7a15e656a3f3cdfbf56299f024e39453f8
diff --git a/examples/dwebp.c b/examples/dwebp.c
index a4b49eb..7cd6413 100644
--- a/examples/dwebp.c
+++ b/examples/dwebp.c
@@ -37,6 +37,11 @@
#include <wincodec.h>
#endif
+#if defined(_WIN32)
+#include <fcntl.h> // for _O_BINARY
+#include <io.h> // for _setmode()
+#endif
+
#include "webp/decode.h"
#include "./example_util.h"
#include "./stopwatch.h"
@@ -431,10 +436,11 @@
return ok;
}
-static void SaveOutput(const WebPDecBuffer* const buffer,
+static int SaveOutput(const WebPDecBuffer* const buffer,
OutputFileFormat format, const char* const out_file) {
FILE* fout = NULL;
int needs_open_file = 1;
+ int use_stdout = !strcmp(out_file, "-");
int ok = 1;
Stopwatch stop_watch;
@@ -444,11 +450,20 @@
#ifdef HAVE_WINCODEC_H
needs_open_file = (format != PNG);
#endif
+ use_stdout &= needs_open_file;
+
+#if defined(_WIN32)
+ if (use_stdout && _setmode(_fileno(stdout), _O_BINARY) == -1) {
+ fprintf(stderr, "Failed to reopen stdout in O_BINARY mode.\n");
+ return -1;
+ }
+#endif
+
if (needs_open_file) {
- fout = fopen(out_file, "wb");
- if (!fout) {
+ fout = use_stdout ? stdout : fopen(out_file, "wb");
+ if (fout == NULL) {
fprintf(stderr, "Error opening output file %s\n", out_file);
- return;
+ return 0;
}
}
@@ -471,18 +486,27 @@
} else if (format == ALPHA_PLANE_ONLY) {
ok &= WriteAlphaPlane(fout, buffer);
}
- if (fout) {
+ if (fout != NULL && fout != stdout) {
fclose(fout);
}
if (ok) {
- printf("Saved file %s\n", out_file);
+ if (fout != stdout) {
+ fprintf(stderr, "Saved file %s\n", out_file);
+ } else {
+ fprintf(stderr, "Saved to stdout\n");
+ }
if (verbose) {
const double write_time = StopwatchReadAndReset(&stop_watch);
- printf("Time to write output: %.3fs\n", write_time);
+ fprintf(stderr, "Time to write output: %.3fs\n", write_time);
}
} else {
- fprintf(stderr, "Error writing file %s !!\n", out_file);
+ if (fout != stdout) {
+ fprintf(stderr, "Error writing to stdout !!\n");
+ } else {
+ fprintf(stderr, "Error writing file %s !!\n", out_file);
+ }
}
+ return ok;
}
static void Help(void) {
@@ -519,6 +543,7 @@
};
int main(int argc, const char *argv[]) {
+ int ok = 0;
const char *in_file = NULL;
const char *out_file = NULL;
@@ -598,7 +623,6 @@
{
Stopwatch stop_watch;
VP8StatusCode status = VP8_STATUS_OK;
- int ok;
size_t data_size = 0;
const uint8_t* data = NULL;
@@ -655,7 +679,7 @@
if (verbose) {
const double decode_time = StopwatchReadAndReset(&stop_watch);
- printf("Time to decode picture: %.3fs\n", decode_time);
+ fprintf(stderr, "Time to decode picture: %.3fs\n", decode_time);
}
end:
free((void*)data);
@@ -667,20 +691,21 @@
}
}
- if (out_file) {
- printf("Decoded %s. Dimensions: %d x %d%s. Now saving...\n", in_file,
- output_buffer->width, output_buffer->height,
+ if (out_file != NULL) {
+ fprintf(stderr, "Decoded %s. Dimensions: %d x %d%s. Now saving...\n",
+ in_file, output_buffer->width, output_buffer->height,
bitstream->has_alpha ? " (with alpha)" : "");
- SaveOutput(output_buffer, format, out_file);
+ ok = SaveOutput(output_buffer, format, out_file);
} else {
- printf("File %s can be decoded (dimensions: %d x %d)%s.\n",
+ fprintf(stderr, "File %s can be decoded (dimensions: %d x %d)%s.\n",
in_file, output_buffer->width, output_buffer->height,
bitstream->has_alpha ? " (with alpha)" : "");
- printf("Nothing written; use -o flag to save the result as e.g. PNG.\n");
+ fprintf(stderr, "Nothing written; "
+ "use -o flag to save the result as e.g. PNG.\n");
}
WebPFreeDecBuffer(output_buffer);
- return 0;
+ return ok ? 0 : -1;
}
//------------------------------------------------------------------------------
diff --git a/man/dwebp.1 b/man/dwebp.1
index 69ee674..2f5186c 100644
--- a/man/dwebp.1
+++ b/man/dwebp.1
@@ -23,6 +23,8 @@
.TP
.BI \-o " string
Specify the name of the output file (as PNG format by default).
+Using "-" as output name will direct output to 'stdout' (this feature
+is not available when using WIC under Windows).
.TP
.B \-bmp
Change the output format to uncompressed BMP.
