catch null vfork_exec_wrapper before it is too late

[ardour.git] / libs / pbd / system_exec.cc

diff --git a/libs/pbd/system_exec.cc b/libs/pbd/system_exec.cc
index 7e94880f858568e372b80db6c859e0d1fa9a888c..01c46aa9eb62b603922aca904a1a3a3e0ceb34cf 100644 (file)
--- a/libs/pbd/system_exec.cc
+++ b/libs/pbd/system_exec.cc
@@ -43,9 +43,12 @@
 #include <sys/resource.h>
 #endif
 
+#include <glibmm/miscutils.h>
 
 #define USE_VFORK
 
+#include "pbd/file_utils.h"
+#include "pbd/search_path.h"
 #include "pbd/system_exec.h"
 
 using namespace std;
@@ -192,8 +195,17 @@ SystemExec::SystemExec (std::string command, const std::map<char, std::string> s
 {
        init ();
        make_argp_escaped(command, subs);
-       cmd = argp[0];
-       // cmd = strdup(argp[0]);
+
+       if (find_file (Searchpath (Glib::getenv ("PATH")), argp[0], cmd)) {
+               // argp[0] exists in $PATH` - set it to the actual path where it was found
+               free (argp[0]);
+               argp[0] = strdup(cmd.c_str ());
+       }
+       // else argp[0] not found in path - leave it as-is, it might be an absolute path
+
+       // Glib::find_program_in_path () is only available in Glib >= 2.28
+       // cmd = Glib::find_program_in_path (argp[0]);
+
        make_envp();
 }
 
@@ -265,9 +277,6 @@ SystemExec::make_argp_escaped(std::string command, const std::map<char, std::str
                }
        }
        argp[n] = NULL;
-
-       char *p = argp[0];
-       n = 0;
 }
 
 SystemExec::~SystemExec ()
@@ -275,13 +284,13 @@ SystemExec::~SystemExec ()
        terminate ();
        if (envp) {
                for (int i=0;envp[i];++i) {
-                 free(envp[i]);
+                       free(envp[i]);
                }
                free (envp);
        }
        if (argp) {
                for (int i=0;argp[i];++i) {
-                 free(argp[i]);
+                       free(argp[i]);
                }
                free (argp);
        }
@@ -796,6 +805,10 @@ SystemExec::start (int stderr_mode, const char *vfork_exec_wrapper)
 #else
        signal(SIGPIPE, SIG_DFL);
 #endif
+       if (!vfork_exec_wrapper) {
+               error << _("Cannot start external process, no vfork wrapper") << endmsg;
+               return -1;
+       }
 
        int good_fds[2] = { pok[1],  -1 };
        close_allv(good_fds);
@@ -858,7 +871,16 @@ SystemExec::output_interposer()
        for (;fcntl(rfd, F_GETFL)!=-1;) {
                r = read(rfd, buf, sizeof(buf));
                if (r < 0 && (errno == EINTR || errno == EAGAIN)) {
-                       ::usleep(1000);
+                       fd_set rfds;
+                       struct timeval tv;
+                       FD_ZERO(&rfds);
+                       FD_SET(rfd, &rfds);
+                       tv.tv_sec = 0;
+                       tv.tv_usec = 10000;
+                       int rv = select(1, &rfds, NULL, NULL, &tv);
+                       if (rv == -1) {
+                               break;
+                       }
                        continue;
                }
                if (r <= 0) {