Clean up Transport::execute() and callers.

- Ensure that the real exit code of the child program is retrieved
  using WEXITSTATUS().

- Centralise the handling of code 127, which means that the child
  shell process could not execute its child (ssh, rsync, or curl.)

Signed-off-by: Russell Steicke <russells@adelie.cx>

src/Transport.cpp

@@ -30,6 +30,10 @@
 #include <iostream>
 #include <stdlib.h>
 #include <util.h>
+#include <string.h>
+#include <errno.h>
+#include <text.h>
+#include <i18n.h>
 #include <Transport.h>
 #include <TransportSSH.h>
 #include <TransportRSYNC.h>
@@ -87,7 +91,17 @@ int Transport::execute()
         it->append("\"");
     }
   }
-  return ::execute(_executable, _arguments);
+  int result = ::execute (_executable, _arguments);
+  int err;
+  switch (result) {
+  case 127:
+    throw format (STRING_TRANSPORT_NORUN, _executable);
+  case -1:
+    err = errno;
+    throw format (STRING_TRANSPORT_NOFORK, _executable, ::strerror(err));
+  default:
+    return result;
+  }
 }
 
 ////////////////////////////////////////////////////////////////////////////////

src/TransportCurl.cpp

@@ -80,14 +80,8 @@ void TransportCurl::send(const std::string& source)
     _arguments.push_back (_uri._protocol + "://" + _uri._host + "/" + _uri._path);
   }
 
-  int result = execute();
-  if (result)
-  {
-    if (result == 127) // command not found
-      throw std::string (STRING_TRANSPORT_CURL_NORUN);
-    else
-      throw std::string (STRING_TRANSPORT_CURL_FAIL);
-  }
+  if (execute ())
+    throw std::string (STRING_TRANSPORT_CURL_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -148,14 +142,8 @@ void TransportCurl::recv(std::string target)
 
   _arguments.insert (_arguments.end (), targetargs.begin (), targetargs.end ());
 
-  int result = execute();
-  if (result)
-  {
-    if (result == 127) // command not found
-      throw std::string (STRING_TRANSPORT_CURL_NORUN);
-    else
-      throw std::string (STRING_TRANSPORT_CURL_FAIL);
-  }
+  if (execute ())
+    throw std::string (STRING_TRANSPORT_CURL_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////

src/TransportRSYNC.cpp

@@ -65,8 +65,8 @@ void TransportRSYNC::send(const std::string& source)
 		_arguments.push_back (_uri._host + "::" + _uri._path);
 	}
 
-	if (execute())
-    throw std::string (STRING_TRANSPORT_RSYNC_NORUN);
+	if (execute ())
+    throw std::string (STRING_TRANSPORT_RSYNC_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -95,8 +95,8 @@ void TransportRSYNC::recv(std::string target)
 
 	_arguments.push_back (target);
 
-	if (execute())
-    throw std::string (STRING_TRANSPORT_RSYNC_NORUN);
+	if (execute ())
+    throw std::string (STRING_TRANSPORT_RSYNC_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////

src/TransportSSH.cpp

@@ -67,8 +67,8 @@ void TransportSSH::send(const std::string& source)
 		_arguments.push_back (_uri._host + ":" + escape (_uri._path, ' '));
 	}
 
-	if (execute())
-    throw std::string (STRING_TRANSPORT_SSH_NORUN);
+	if (execute ())
+		throw std::string (STRING_TRANSPORT_SSH_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -100,8 +100,8 @@ void TransportSSH::recv(std::string target)
 
 	_arguments.push_back (target);
 
-	if (execute())
-    throw std::string (STRING_TRANSPORT_SSH_NORUN);
+	if (execute ())
+		throw std::string (STRING_TRANSPORT_SSH_FAIL);
 }
 
 ////////////////////////////////////////////////////////////////////////////////

src/en-US.h

@@ -837,15 +837,16 @@
 #define STRING_TEXT_AMBIGUOUS        "Ambiguous {1} '{2}' - could be either of "
 
 // Transport
+#define STRING_TRANSPORT_NORUN       "Could not run '{1}'.  Is it installed, and available in $PATH?"
+#define STRING_TRANSPORT_NOFORK      "Could not run '{1}': {2}. Are you out of system resources?"
 #define STRING_TRANSPORT_URI_NODIR   "The uri '{1}' does not appear to be a directory."
 #define STRING_TRANSPORT_CURL_URI    "When using the 'curl' protocol, the uri must contain a hostname."
 #define STRING_TRANSPORT_CURL_WILDCD "When using the 'curl' protocol, wildcards are not supported."
-#define STRING_TRANSPORT_CURL_NORUN  "Could not run curl.  Is it installed, and available in $PATH?"
 #define STRING_TRANSPORT_CURL_FAIL   "Curl failed, see output above."
 #define STRING_TRANSPORT_RSYNC_URI   "When using the 'rsync' protocol, the uri must contain a hostname."
-#define STRING_TRANSPORT_RSYNC_NORUN "Could not run rsync.  Is it installed, and available in $PATH?"
+#define STRING_TRANSPORT_RSYNC_FAIL  "rsync failed, see output above."
 #define STRING_TRANSPORT_SSH_URI     "When using the 'ssh' protocol, the uri must contain a hostname."
-#define STRING_TRANSPORT_SSH_NORUN   "Could not run ssh.  Is it installed, and available in $PATH?"
+#define STRING_TRANSPORT_SSH_FAIL    "ssh failed, see output above."
 
 // Uri
 #define STRING_URI_QUOTES            "Could not parse uri '{1}', wrong usage of single quotes."

src/es-ES.h

@@ -853,15 +853,16 @@
 #define STRING_TEXT_AMBIGUOUS        "Ambiguo {1} '{2}' - puede ser "
 
 // Transport
+#define STRING_TRANSPORT_NORUN       "Could not run '{1}'.  Is it installed, and available in $PATH?"
+#define STRING_TRANSPORT_NOFORK      "Could not run '{1}': {2}. Are you out of system resources?"
 #define STRING_TRANSPORT_URI_NODIR   "El uri '{1}' no parece ser un directorio."
 #define STRING_TRANSPORT_CURL_URI    "Cuando se usa el protocolo 'curl' el uri debe contener un nombre de máquina."
 #define STRING_TRANSPORT_CURL_WILDCD "Cuando se usa el protocolo 'curl' no están soportados los comodines."
-#define STRING_TRANSPORT_CURL_NORUN  "No se pudo lanzar curl. ¿Está instalado y disponible en $PATH?"
 #define STRING_TRANSPORT_CURL_FAIL   "Curl falló, consulte los mensajes precedentes."
 #define STRING_TRANSPORT_RSYNC_URI   "Cuando se usa el protocolo 'rsync' el uri debe contener un nombre de máquina."
-#define STRING_TRANSPORT_RSYNC_NORUN "No se pudo lanzar rsync. ¿Está instalado y disponible en $PATH?"
+#define STRING_TRANSPORT_RSYNC_FAIL  "rsync failed, see output above."
 #define STRING_TRANSPORT_SSH_URI     "Cuando se usa el protocolo 'ssh' el uri debe contener un nombre de máquina."
-#define STRING_TRANSPORT_SSH_NORUN   "No se pudo lanzar ssh. ¿Está instalado y disponible en $PATH?"
+#define STRING_TRANSPORT_SSH_FAIL    "ssh failed, see output above."
 
 // Uri
 #define STRING_URI_QUOTES            "No se pudo interpretar el uri '{1}', uso erróneo de comillas simples."

src/util.cpp

@@ -417,7 +417,7 @@ int execute(const std::string& executable, std::vector<std::string> arguments)
     cmdline += " " + (std::string)*it;
   }
 
-	context.debug ("Executing: " + std::string(shell) + " " + std::string(opt) + " " + cmdline);
+  context.debug ("Executing: " + std::string(shell) + " " + std::string(opt) + " " + cmdline);
 
   pid_t child_pid = fork();
 
@@ -435,6 +435,10 @@ int execute(const std::string& executable, std::vector<std::string> arguments)
 
     exit(ret);
   }
+  else if (child_pid == -1)
+  {
+    return -1;
+  }
   else
   {
     // this is done by the parent process
@@ -445,7 +449,7 @@ int execute(const std::string& executable, std::vector<std::string> arguments)
     if (pid == -1)
       return -1;
     else
-      return child_status;
+      return WEXITSTATUS (child_status);
   }
 }