[dpdk-dev] [PATCH] pmdinfogen: allow using stdin and stdout

[Bruce Richardson <bruce.richardson@intel.com>]

Rather than having to work off files all the time, allow stdin and stdout
to be used as the source and destination for pmdinfogen. This will allow
other possible usages from scripts, e.g. taking files from ar archive and
building a single .pmd.c file from all the .o files in it.

	for f in `ar t librte_pmd_xyz.a` ; do
		ar p librte_pmd_xyz.a $f | pmdinfogen - - >> xyz_info.c
	done

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 buildtools/pmdinfogen/pmdinfogen.c | 44 +++++++++++++++++++++++++++++++-------
 1 file changed, 36 insertions(+), 8 deletions(-)

diff --git a/buildtools/pmdinfogen/pmdinfogen.c b/buildtools/pmdinfogen/pmdinfogen.c
index b07dbcf4b..45b267346 100644
--- a/buildtools/pmdinfogen/pmdinfogen.c
+++ b/buildtools/pmdinfogen/pmdinfogen.c
@@ -26,6 +26,7 @@
 #define ADDR_SIZE 32
 #endif
 
+static int use_stdin, use_stdout;
 
 static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
 {
@@ -39,11 +40,32 @@ static void *grab_file(const char *filename, unsigned long *size)
 {
 	struct stat st;
 	void *map = MAP_FAILED;
-	int fd;
+	int fd = -1;
+
+	if (!use_stdin) {
+		fd = open(filename, O_RDONLY);
+		if (fd < 0)
+			return NULL;
+	} else {
+		/* from stdin, use a temporary file to mmap */
+		FILE *infile;
+		char buffer[1024];
+		size_t n;
+
+		infile = tmpfile();
+		if (infile == NULL) {
+			perror("tmpfile");
+			return NULL;
+		}
+		while (!feof(stdin)) {
+			n = fread(buffer, 1, sizeof(buffer), stdin);
+			if (fwrite(buffer, 1, n, infile) != n)
+				goto failed;
+		}
+		fflush(infile);
+		fd = fileno(infile);
+	}
 
-	fd = open(filename, O_RDONLY);
-	if (fd < 0)
-		return NULL;
 	if (fstat(fd, &st))
 		goto failed;
 
@@ -358,10 +380,14 @@ static void output_pmd_info_string(struct elf_info *info, char *outfile)
 	struct rte_pci_id *pci_ids;
 	int idx = 0;
 
-	ofd = fopen(outfile, "w+");
-	if (!ofd) {
-		fprintf(stderr, "Unable to open output file\n");
-		return;
+	if (use_stdout)
+		ofd = stdout;
+	else {
+		ofd = fopen(outfile, "w+");
+		if (!ofd) {
+			fprintf(stderr, "Unable to open output file\n");
+			return;
+		}
 	}
 
 	drv = info->drivers;
@@ -411,6 +437,8 @@ int main(int argc, char **argv)
 			basename(argv[0]));
 		exit(127);
 	}
+	use_stdin = !strcmp(argv[1], "-");
+	use_stdout = !strcmp(argv[2], "-");
 	parse_elf(&info, argv[1]);
 
 	if (locate_pmd_entries(&info) < 0)
-- 
2.14.3