Merge pull request #4 from astephens25/amqpsend-stdin

Added stdin reading capability to amqpsend

README.rst

@@ -57,7 +57,7 @@ You may also pass a filename as input.
 
 $ ./amqpsend --help::
   
-  Usage: ./amqpsend [options] exchange routingkey [msg]
+  Usage: ./amqpsend [options] exchange routingkey [message]
   Options:
     --host/-h host         specify the host (default: "amqpbroker")
     --port/-P port         specify AMQP port (default: 5672)
@@ -71,8 +71,12 @@ $ ./amqpsend --help::
   The following environment variables may also be set:
     AMQP_HOST, AMQP_PORT, AMQP_VHOST, AMQP_USER, AMQP_PASSWORD, AMQP_PERSISENT
   Acceptable values for AMQP_PERSISENT are '1' (No Persist) and '2' (Persist)
+
+  With no -f option and no message, message contents will be read from standard
+  input. 
   
   Example:
   $ amqpsend -h amqp.example.com -P 5672 amq.fanout mykey "HELLO AMQP"
   $ amqpsend -h amqp.example.com -P 5672 amq.fanout mykey -f /etc/hosts
+  $ echo "HELLO AMQP" | amqpsend -h amqp.example.com -P 5672 amq.fanout mykey
   

amqpsend.c

@@ -62,6 +62,8 @@
 #include <assert.h>
 #include <getopt.h>
 
+#define BUFFERSIZE 8096
+
 // from "example_utils.c"
 void die_on_error(int x, char const *context) {
   if (x < 0) {
@@ -115,7 +117,8 @@ void die_on_amqp_error(amqp_rpc_reply_t x, char const *context) {
 }
 
 void print_help(const char *program_name) {
-    fprintf(stderr, "Usage: %s [options] exchange routingkey [msg]\n", program_name);
+    fprintf(stderr, "Usage: %s [options] exchange routingkey [message]\n", program_name);
+    fprintf(stderr, "\n");
     fprintf(stderr, "Options:\n");
     fprintf(stderr, "  --host/-h host         specify the host (default: \"amqpbroker\")\n");
     fprintf(stderr, "  --port/-P port         specify AMQP port (default: 5672)\n");
@@ -128,10 +131,14 @@ void print_help(const char *program_name) {
     fprintf(stderr, "\n");
     fprintf(stderr, "The following environment variables may also be set:\n");
     fprintf(stderr, "  AMQP_HOST, AMQP_PORT, AMQP_VHOST, AMQP_USER, AMQP_PASSWORD, AMQP_PERSISTENT\n");
-    fprintf(stderr, "Acceptable values for AMQP_PERSISENT are '1' (Not Persistent) and '2' (Persistent)\n\n");
+    fprintf(stderr, "Acceptable values for AMQP_PERSISENT are '1' (Not Persistent) and '2' (Persistent)\n");
+    fprintf(stderr, "\n");
+    fprintf(stderr, "With no -f option and no message, message contents will be read from standard input.\n"); 
+    fprintf(stderr, "\n");
     fprintf(stderr, "Example:\n");
     fprintf(stderr, "$ amqpsend -h amqp.example.com -P 5672 amq.fanout mykey \"HELLO AMQP\"\n");
-    fprintf(stderr, "$ amqpsend -h amqp.example.com -P 5672 amq.fanout mykey -f /etc/hosts\n\n");
+    fprintf(stderr, "$ amqpsend -h amqp.example.com -P 5672 amq.fanout mykey -f /etc/hosts\n");
+    fprintf(stderr, "$ echo \"HELLO AMQP\" | amqpsend -h amqp.example.com -P 5672 amq.fanout mykey\n\n");
 }
 
 // shamelessly taken from the public domain
@@ -148,12 +155,30 @@ int load_file_into_memory(const char *filename,  char **result) {
   *result = (char *)malloc(size);
   if(size != fread(*result, sizeof(char), size, f)) {
     free(*result);
+    fclose(f);
     return -2;
   }
   fclose(f);
   return size;
 }
 
+int load_stdin_into_memory(char **file) {
+  int size = 0, read = 0;
+  char *buffer = (char *)malloc(sizeof(char) * BUFFERSIZE);
+  do {
+    size += (read = fread(buffer, sizeof(char), BUFFERSIZE, stdin));
+    if (ferror(stdin)) {
+      free(*file);
+      free(buffer);
+      return -1;
+    }
+    *file = (char *)realloc((void *)*file, sizeof(char) * size);
+    memcpy(*file + (sizeof(char) * (size - read)), buffer, read);
+  } while (read == BUFFERSIZE);   
+  free(buffer);
+  return size;
+}
+
 int main(int argc, char **argv) {
   char const *hostname = "amqpbroker"; // amqp hostname
   int port = 5672; // amqp port
@@ -237,14 +262,26 @@ int main(int argc, char **argv) {
     }
   }
 
-  if ((argc-optind) < 2 || (NULL == filename && (argc-optind) < 3)) {
+  // if ((argc-optind) < 2 || (NULL == filename && (argc-optind) < 3)) {
+  if ((argc-optind) < 2) {
     print_help(argv[0]);
     return 1;
   }
   exchange = argv[optind];
   routingkey = argv[optind+1];
   if(NULL == filename) {
-    messagebody = amqp_cstring_bytes(argv[optind+2]);
+    if ((argc-optind) >= 3) {
+      messagebody = amqp_cstring_bytes(argv[optind+2]);
+    } else {
+      char *file = NULL;
+      int size = load_stdin_into_memory(&file);
+      if (size >= 0) {
+        messagebody = (amqp_bytes_t) {.len = size, .bytes = (void *)file};
+      } else {
+        fprintf(stderr, "Error reading from STDIN\n");
+        exit(size);
+      }
+    }
   } else {
     char *bytes = NULL;
     int size = load_file_into_memory(filename, &bytes);