X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=server%2Fsensors%2Fpiped.c;fp=server%2Fsensors%2Fpiped.c;h=6444e8bd75feb658ded19c8fbf70e61423e319e3;hb=289794ba2dcbe6234e25e5d00531b26baee342b7;hp=0000000000000000000000000000000000000000;hpb=71c13fe3c04db7f93a69cbc6a6c7c3dc2393bf3f;p=matches%2FMCTX3420.git

diff --git a/server/sensors/piped.c b/server/sensors/piped.c
new file mode 100644
index 0000000..6444e8b
--- /dev/null
+++ b/server/sensors/piped.c
@@ -0,0 +1,101 @@
+/**
+ * @file piped.h
+ * @brief Sensor run by an external process and sent to this one through a pipe
+ * PURELY INCLUDED FOR TESTING PURPOSES
+ *	This will work with any sensor that can unbuffer stdout
+ * ... So, although it's not recommended, you could write a sensor purely in something like python
+ *	   The FastCGI process will handle all the time stamps and stuff
+ */
+
+#include "../log.h"
+#include "../common.h"
+
+#include "piped.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/signal.h>
+#include <ctype.h>
+
+
+typedef struct
+{
+	int pid;
+	int sv[2];
+	FILE * stream;
+	
+} Piped;
+
+static Piped g_piped[PIPED_MAX];
+static int g_num_piped = 0;
+
+bool Piped_Init(const char * name, int id)
+{
+	if (++g_num_piped > PIPED_MAX)
+	{
+		Fatal("Too many sensors; Increase PIPED_MAX from %d in piped.h and recompile", PIPED_MAX);
+	}
+
+	if (socketpair(AF_UNIX, SOCK_STREAM, 0, g_piped[id].sv) != 0)
+			Fatal("socketpair failed - %s", strerror(errno));
+
+	g_piped[id].pid = fork();
+	if (g_piped[id].pid == 0)
+	{
+		dup2(g_piped[id].sv[0], fileno(stdin));
+		dup2(g_piped[id].sv[0], fileno(stdout));
+
+		if (access(name, X_OK) == 0) //Check we STILL have permissions to start the file
+		{
+			execl(name, name, (char*)(NULL)); ///Replace process with desired executable
+			//execv(executablePath,arguments); ///Replace process with desired executable
+		}
+		else
+		{
+			Fatal("Can't execute file %s", name);
+		}
+		Fatal("execl error - %s", strerror(errno));
+	}
+	else
+	{
+		g_piped[id].stream = fdopen(g_piped[id].sv[1], "r");
+		setbuf(g_piped[id].stream, NULL);
+	}
+	return true;
+	
+}
+
+bool Piped_Read(int id, double * value)
+{
+	if (g_piped[id].stream == NULL)
+		return false;
+
+	static char line[BUFSIZ];
+	
+	fgets(line, BUFSIZ, g_piped[id].stream);
+	int len = strlen(line);
+	//Log(LOGDEBUG, "Read %s (%d) chars", line, len);
+	while (--len >= 0 && len < BUFSIZ && isspace(line[len]))
+	{
+		line[len] = '\0';
+	}
+	char * end = line;
+	*value = strtod(line, &end);
+	if (*end != '\0')
+	{
+		Log(LOGERR, "Couldn't interpret %s as double - %s", line, strerror(errno));
+		return false;
+	}
+	return true;
+}
+
+bool Piped_Cleanup(int id)
+{
+	fclose(g_piped[id].stream);
+	if (kill(g_piped[id].pid, 15) != 0)
+	{
+		Log(LOGWARN, "Couldn't kill piped %d - %s", g_piped[id].pid, strerror(errno));
+		return false;
+	}
+	return true;
+}