display info screen upon exit of a command invoked by lcdexec

clients/lcdexec/lcdexec.c

@@ -14,6 +14,7 @@
 #include <string.h>
 #include <sys/utsname.h>
 #include <signal.h>
+#include <time.h>
 #include <sys/wait.h>
 
 #include "getopt.h"
@@ -31,6 +32,17 @@
 
 #define DEFAULT_CONFIGFILE	SYSCONFDIR "/lcdexec.conf"
 
+/** information about a process started by lcdexec */
+typedef struct ProcInfo {
+	struct ProcInfo *next;	/**< pointer to the next ProcInfo entry */
+	const MenuEntry *cmd;	/**< pointer to the corresponding menu entry */
+	pid_t pid;		/**< PID the process was started with */
+	time_t starttime;	/**< start time of the process */
+	time_t endtime;		/**< finishing time of the process */
+	int status;		/**< exit status of the process */
+	int shown;		/**< tell if the info has been shown to the user */
+} ProcInfo;
+
 
 char * help_text =
 "lcdexec - LCDproc client to execute commands from the LCDd menu\n"
@@ -53,8 +65,8 @@ char *progname = "lcdexec";
 /* Variables set by config */
 #define UNSET_INT -1
 #define UNSET_STR "\01"
-char * configfile = NULL;
+char *configfile = NULL;
-char * address = NULL;
+char *address = NULL;
 int port = UNSET_INT;
 int foreground = FALSE;
 static int report_level = UNSET_INT;
@@ -62,23 +74,26 @@ static int report_dest = UNSET_INT;
 char *displayname = NULL;
 char *default_shell = NULL;
 
-MenuEntry *main_menu;
-
 /* Other variables */
-int sock = -1;
+MenuEntry *main_menu = NULL;	/**< pointer to the main menu */
+ProcInfo *proc_queue = NULL;	/**< pointer to the list of executed processes */
+
+int lcd_wid = 0;		/**< LCD display width reported by the server */
+int lcd_hgt = 0;		/**< LCD display height reported by the server */
+
+int sock = -1;			/**< socket to connect to server */
+
 
 /* Function prototypes */
+static void sigchld_handler(int);
 static int process_command_line(int argc, char **argv);
 static int process_configfile(char * configfile);
 static int connect_and_setup(void);
 static int process_response(char *str);
 static int exec_command(MenuEntry *cmd);
+static int show_procinfo_msg(ProcInfo *p);
 static int main_loop(void);
 
-static pid_t last_child_pid = 0;
-static int last_child_status = 0;
-static void sigchld_handler(int);
-
 #define CHAIN(e,f) { if (e>=0) { e=(f); }}
 #define CHAIN_END(e) { if (e<0) { report(RPT_CRIT,"Critical error, abort"); exit(e); }}
 
@@ -127,25 +142,17 @@ static void sigchld_handler(int signal)
 	pid_t pid;
 	int status;
 
+	/* wait for the child that was signalled as finished */
 	if ((pid = wait(&status)) != -1) {
-    last_child_pid = pid;
+		ProcInfo *p;
-    last_child_status = status;
 
-  // better:
+		/* fill the procinfo structure with the necessary information */
-  // - build a queue with (pid,status) pairs (here)
+		for (p = proc_queue; p != NULL; p = p->next) {
-  // - show a screen for each pair (in the main_loop)
+			if (p->pid == pid) {
-  // - remove elements from the queue which are shown (dito)
+				p->status = status;
-  // even better:
+				p->endtime = time(NULL);
-  // - build a queue of (pid, name) on exec (in exec command)
+			}
-  // - display a screen about start (in main_loop)
+		}	
-  // - add status to the appropriate queue element (here)
-  // - display screen about exit (in main_loop)
-  // - remove elements from the queue which are shown (dito)
-  // screens should be shown in main_loop to 
-  // - not show a startup screen when the command is already done
-  //   (note: danger for a race between sig_handler and main_loop,
-  //    in the 1st case above, since both work on the queue)
-  // - automatically time screens  
 	}
 }
 
@@ -314,14 +321,14 @@ static int connect_and_setup(void)
 
 static int process_response(char *str)
 {
-	char *argv[15];
+	char *argv[20];
 	int argc;
 	char *str2 = strdup(str); /* get_args modifies str2 */
 
 	report(RPT_DEBUG, "Server said: \"%s\"", str);
 
 	/* Check what the server just said to us... */
-	argc = get_args(argv, str2, 10);
+	argc = get_args(argv, str2, sizeof(argv)/sizeof(argv[0]));
 	if (argc < 1) {
 		free(str2);
 		return 0;
@@ -358,6 +365,23 @@ static int process_response(char *str)
 			; /* Ignore other menuevents */
 		}
 	}
+	else if (strcmp(argv[0], "connect") == 0) {
+		int a;
+
+		/* determine display height and width */
+		for (a = 1; a < argc; a++) {
+			if (strcmp(argv[a], "wid") == 0)
+				lcd_wid = atoi(argv[++a]);
+			else if (strcmp(argv[a], "hgt") == 0)
+				lcd_hgt = atoi(argv[++a]);
+		}
+	}
+	else if (strcmp(argv[0], "bye") == 0) {
+		// TODO: make it better
+		report(RPT_INFO, "Server said: \"%s\"", str);
+		sock_close(sock);
+		exit(EXIT_SUCCESS);
+	}	
 	else if (strcmp(argv[0], "huh?") == 0) {
 		/* Report errors */
 		report(RPT_WARNING, "Server said: \"%s\"", str);
@@ -375,6 +399,8 @@ static int exec_command(MenuEntry *cmd)
 	if ((cmd != NULL)  && (menu_command(cmd) != NULL)) {
 		const char *command = menu_command(cmd);
 		const char *argv[4];
+		pid_t pid;
+		ProcInfo *p;
 
 		report(RPT_NOTICE, "Executing: %s", command);
 
@@ -383,18 +409,27 @@ static int exec_command(MenuEntry *cmd)
 		argv[2] = command;
 		argv[3] = NULL;
 
-		switch (fork()) {
+		switch (pid = fork()) {
 		  case 0:
-			/* We're the child. Execute the command. */
+			/* We're the child: execute the command */
 			execv(argv[0], (char **) argv);
 			exit(0);
 			break;
+		  default:
+			/* We're the parent: setup the ProcInfo structure */
+			p = calloc(1, sizeof(ProcInfo));
+			if (p != NULL) {
+				p->cmd = cmd;
+				p->pid = pid;
+				p->starttime = time(NULL);
+				/* prepend it to existing queue atomically */
+				p->next = proc_queue;
+				proc_queue = p;
+			}
+	        	break;
 		  case -1:
 			report(RPT_ERR, "Could not fork");
 			return -1;
-		  default:
-			/* We're the parent */
-	        	break;
 		}
 		return 0;
 	}
@@ -402,25 +437,119 @@ static int exec_command(MenuEntry *cmd)
 }
 
 
+static int show_procinfo_msg(ProcInfo *p)
+{
+	if ((p != NULL) && (lcd_wid > 0) && (lcd_hgt > 0)) {
+		if (p->endtime > 0) {
+			sock_printf(sock, "screen_add [%u]\n", p->pid);
+			sock_printf(sock, "screen_set [%u] -name {lcdexec [%u]}"
+					  " -priority alert -timeout %d"
+					  " -heartbeat off\n",
+					p->pid, p->pid, 8*8);
+
+			if (lcd_hgt > 2) {
+				sock_printf(sock, "widget_add [%u] t title\n", p->pid);
+				sock_printf(sock, "widget_set [%u] t {%s}\n", p->pid, p->cmd->displayname);
+				sock_printf(sock, "widget_add [%u] s1 string\n", p->pid);
+				sock_printf(sock, "widget_add [%u] s2 string\n", p->pid);
+				sock_printf(sock, "widget_add [%u] s3 string\n", p->pid);
+
+				sock_printf(sock, "widget_set [%u] s1 1 2 {[%u] finished%s}\n",
+						p->pid, p->pid, (WIFSIGNALED(p->status) ? "," : ""));
+
+				if (WIFEXITED(p->status)) {
+					if (WEXITSTATUS(p->status) == EXIT_SUCCESS) {
+						sock_printf(sock, "widget_set [%u] s2 1 3 {successfully.}\n",
+								p->pid);
+					}
+					else {
+						sock_printf(sock, "widget_set [%u] s2 1 3 {with code 0x%02X.}\n",
+								p->pid, WEXITSTATUS(p->status));
+					}			
+				}
+				else if (WIFSIGNALED(p->status)) {
+					sock_printf(sock, "widget_set [%u] s2 1 3 {killed by SIG %d.}\n",
+						p->pid, WTERMSIG(p->status));
+				}
+
+				sock_printf(sock, "widget_set [%u] s3 1 4 {Exec time: %lds}\n",
+						p->pid, p->endtime - p->starttime);
+			}
+			else {
+				sock_printf(sock, "widget_add [%u] s1 string\n", p->pid);
+				sock_printf(sock, "widget_add [%u] s2 string\n", p->pid);
+				sock_printf(sock, "widget_set [%u] s1 1 1 {%s}\n",
+						p->pid, p->cmd->displayname);
+				if (WIFEXITED(p->status)) {
+					if (WEXITSTATUS(p->status) == EXIT_SUCCESS) {
+						sock_printf(sock, "widget_set [%u] s2 1 2 {succeeded}\n",
+								p->pid, p->status);
+					}
+					else {
+						sock_printf(sock, "widget_set [%u] s2 1 2 {finished (0x%02X)}\n",
+								p->pid, p->status);
+					}
+				}
+				else if (WIFSIGNALED(p->status)) {
+					sock_printf(sock, "widget_set [%u] s2 1 2 {killed by SIG %d}\n",
+							p->pid, WTERMSIG(p->status));
+				
+				}
+			}
+		}
+	}
+	return 1;
+}
+
+
 static int main_loop(void)
 {
 	int num_bytes;
 	char buf[100];
-	int w = 0;
+	int keepalive_delay = 0;
+	int status_delay = 0;
 
 	/* Continuously check if we get a menu event... */
-
 	while ((num_bytes = sock_recv_string(sock, buf, sizeof(buf)-1)) >= 0) {
 		if (num_bytes == 0) {
+			ProcInfo *p;
+
+			/* wait for 1/10th of a second */
 			usleep(100000);
 
-			/* Send an empty line every 3 seconds to make sure the server still exists */
+			/* send an empty line every 3 seconds to make sure the server still exists */
-			if (w++ >= 30) {
+			if (keepalive_delay++ >= 30) {
-				w = 0;
+				keepalive_delay = 0;
 				if (sock_send_string(sock, "\n") < 0) {
 					break; /* Out of while loop */
 				}
 			}
+
+			/* check for a screen to show and procinfo deletion every second */
+			if (status_delay++ >= 10) {
+				status_delay = 0;
+
+				/* delete the ProcInfo from the queue */
+				for (p = proc_queue; p != NULL; p = p->next) {
+					ProcInfo *pn = p->next;
+
+					if ((pn != NULL) && (pn->shown)) {
+						p->next = pn->next;
+						free(pn);
+					}
+				}
+				/* deleting queue head is special */
+				if ((proc_queue != NULL) && (proc_queue->shown)) {
+					p = proc_queue;
+					proc_queue = proc_queue->next;
+					free(p);
+				}
+
+				/* look for a process to display, display it & mark it as shown */
+				for (p = proc_queue; p != NULL; p = p->next) {
+					p->shown |= show_procinfo_msg(p);
+				}
+			}	
 		}
 		else {
 			process_response(buf);
@@ -430,3 +559,4 @@ static int main_loop(void)
 	report(RPT_ERR, "Server disconnected (or connection error)");
 	return 0;
 }
+