Make opening/closing/releasing resources available from signal handler.

[wsti_so.git] / src / process1.c

diff --git a/src/process1.c b/src/process1.c
index b5004830f5c9c43e4aebc60df07a0cf1828e83ea..ad4b9111984c64b4079a78e32a41f912fcf965de 100644 (file)
--- a/src/process1.c
+++ b/src/process1.c
@@ -11,22 +11,44 @@
 /** If buffer is too small to hold entire string, it is incremented by this value */
 #define BUFFER_STEP 16
 
+/** Buffer used to store line of characters */
+char * buffer = NULL;
+
+/** Named pipe used to communnicate with process2 */
+char * write_pipe = "/tmp/process1pipe";
+
+/** File descriptor of pipe */
+int file_descriptor;
+
 /**
  * Handler for signals.
  */
 void sig_handler(int signo)
 {
        if (signo == SIGUSR1) {
-               fprintf(stderr, "[%s] SIGUSR1!\n", "process1");
+               fprintf(stderr, "[%s] Received SIGUSR1!\n", "process1");
        }
-       else if (signo == SIGUSR2) {
-               fprintf(stderr, "[%s] SIGUSR2!\n", "process1");
+       else if (signo == SIGQUIT) {
+               fprintf(stderr, "[%s] Received SIGQUIT!\n", "process1");
+               fprintf(stderr, "[%s] > Releasing resources\n", "process1");
+               close(write_pipe);
+               unlink(write_pipe);
+
+               if (buffer) {
+                       free(buffer);
+                       buffer = NULL;
+               }
+               exit(0);
        }
        else if (signo == SIGINT) {
-               fprintf(stderr, "[%s] SIGINT!\n", "process1");
+               fprintf(stderr, "[%s] Received SIGINT!\n", "process1");
+               fprintf(stderr, "[%s] > Closing pipe\n", "process1");
+               close(write_pipe);
        }
        else if (signo == SIGCONT) {
-               fprintf(stderr, "[%s] SIGCONT!\n", "process1");
+               fprintf(stderr, "[%s] Received SIGCONT!\n", "process1");
+               fprintf(stderr, "[%s] > Opening pipe\n", "process1");
+               file_descriptor = open(write_pipe, O_WRONLY);
        }
 }
 
@@ -38,9 +60,6 @@ int main(void) {
        /** Currently fetched from stdin character */
        int c;
 
-       /** Buffer used to store line of characters */
-       char * buffer = NULL;
-
        /** Current buffer length*/
        int buffer_length = 0;
 
@@ -53,12 +72,6 @@ int main(void) {
         */
        char * tmp = NULL;
 
-       /** Named pipe used to communnicate with process2 */
-       char * write_pipe = "/tmp/process1pipe";
-
-       /** File descriptor of pipe */
-       int file_descriptor;
-
        fprintf(stderr, "[%s] Init!\n", "process1");
 
        /**
@@ -67,8 +80,8 @@ int main(void) {
        if (signal(SIGUSR1, sig_handler) == SIG_ERR) {
                fprintf(stderr, "can't catch SIGUSR1\n");
        }
-       if (signal(SIGUSR2, sig_handler) == SIG_ERR) {
-               fprintf(stderr, "can't catch SIGUSR2\n");
+       if (signal(SIGQUIT, sig_handler) == SIG_ERR) {
+               fprintf(stderr, "can't catch SIGQUIT\n");
        }
        if (signal(SIGINT, sig_handler) == SIG_ERR) {
                fprintf(stderr, "can't catch SIGINT\n");
@@ -137,6 +150,7 @@ int main(void) {
                }
        } while(c != EOF);
 
+       /* Release resources in normal program flow exit. */
        close(write_pipe);
        unlink(write_pipe);