From 61f14079d6d16459dfa2b008392fccd78bc423a4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Rafa=C5=82=20D=C5=82ugo=C5=82=C4=99cki?= Date: Sat, 21 Jun 2014 19:51:59 +0200 Subject: [PATCH] Save nearly working queues. --- src/bootstrap.c | 1 + src/process1.c | 53 ++++++++++++++++++++++++++++++------------ src/process2.c | 62 +++++++++++++++++++++++++++++++++++-------------- src/process3.c | 62 ++++++++++++++++++++++++++++++++++++------------- 4 files changed, 130 insertions(+), 48 deletions(-) diff --git a/src/bootstrap.c b/src/bootstrap.c index bca693c..070dac8 100644 --- a/src/bootstrap.c +++ b/src/bootstrap.c @@ -64,6 +64,7 @@ int main(void) { fprintf(stderr, "[%s] Something went wrong when forking %s. Error: %s\n", "bootstrap", processes[i], strerror(errno)); } + sleep(1); } /* All processes should be now spawned. Close bootstrap program. */ diff --git a/src/process1.c b/src/process1.c index 41e0ea4..2492ebe 100644 --- a/src/process1.c +++ b/src/process1.c @@ -9,6 +9,7 @@ #include #include +#include /** If buffer is too small to hold entire string, it is incremented by this value */ @@ -56,22 +57,54 @@ int qid_output1; int qid_output2; struct queue_message { - int signo; + long mtype; + int signo[1]; }; +void notify_other_processes(int signo) { + int i = 0; + struct queue_message msg; + msg.signo[0] = signo; + + for (; i < 3; i++) { + pid_t pid = processes->pids[i]; + // Bleh + if (i != 0 && pid != 0) { + msg.mtype = i+1; + fprintf(stderr, "[%s] Sending message of type (%d) with value %d\n", "process1", msg.mtype, msg.signo[0]); + msgsnd(pid, &msg, sizeof(int), 0); + fprintf(stderr, "[%s] Sending signal %s (%d) to PID: %d\n", "process1", strsignal(SIGUSR1), SIGUSR1, pid); + kill(pid, SIGUSR1); + } + } +} + /** * Handler for signals. */ void sig_handler(int signo) { fprintf(stderr, "[%s] Received %s!\n", "process1", strsignal(signo)); + if (signo == SIGUSR1) { - fprintf(stderr, "[%s] > Notified!\n", "process3"); + fprintf(stderr, "[%s] > Notified!\n", "process1"); + struct queue_message msg; + /* Check queues from both other processes */ + if (msgrcv(processes->pids[1], &msg, sizeof(int), 1, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process1", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } + else if (msgrcv(processes->pids[2], &msg, sizeof(int), 1, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process1", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } } else if (signo == SIGTERM) { - int i = 0; - struct queue_message msg; - msg.signo = signo; + fprintf(stderr, "[%s] > Signalling other processes..\n", "process1"); + processes->pids[1] = 0; + notify_other_processes(signo); fprintf(stderr, "[%s] > Releasing resources\n", "process1"); close(write_pipe); @@ -81,15 +114,6 @@ void sig_handler(int signo) free(buffer); buffer = NULL; } - for (; i < 3; i++) { - pid_t pid = processes->pids[i]; - fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, pid); - // Bleh - if (i != 0) { - msgsnd(pid, &msg, sizeof(msg)); - kill(pid, SIGUSR1); - } - } exit(0); } else if (signo == SIGTSTP) { @@ -152,7 +176,6 @@ int main(void) { fprintf(stderr, "[%s] Shared pid: %d\n", "process1", getpid()); - sleep(1); /** * Register message queue to communicate with other processes */ diff --git a/src/process2.c b/src/process2.c index d8c294b..ca2b3b2 100644 --- a/src/process2.c +++ b/src/process2.c @@ -1,6 +1,8 @@ #include /* exit.. */ #include +/* strsignal... */ +#include /* open/read/write/close */ #include @@ -59,9 +61,28 @@ int qid_output1; int qid_output2; struct queue_message { - int signo; + long mtype; + int signo[1]; }; +void notify_other_processes(int signo) { + int i = 0; + struct queue_message msg; + msg.signo[0] = signo; + + for (; i < 3; i++) { + pid_t pid = processes->pids[i]; + // Bleh + if (i != 1 && pid != 0) { + msg.mtype = i+1; + fprintf(stderr, "[%s] Sending message of type (%d) with value %d\n", "process1", msg.mtype, msg.signo[0]); + msgsnd(pid, &msg, sizeof(msg), 0); + fprintf(stderr, "[%s] Sending signal %s (%d) to PID: %d\n", "process2", strsignal(SIGUSR1), SIGUSR1, pid); + kill(pid, SIGUSR1); + } + } +} + /** * Handler for signals. */ @@ -70,37 +91,45 @@ void sig_handler(int signo) fprintf(stderr, "[%s] Received %s!\n", "process2", strsignal(signo)); if (signo == SIGUSR1) { fprintf(stderr, "[%s] > Notified!\n", "process2"); + struct queue_message msg; + /* Check queues from both other processes */ + if (msgrcv(processes->pids[0], &msg, sizeof(int), 2, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process2", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } + else if (msgrcv(processes->pids[2], &msg, sizeof(int), 2, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process2", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } } else if (signo == SIGTERM) { - int i = 0; - struct queue_message msg; - msg.signo = signo; + fprintf(stderr, "[%s] > Signalling other processes..\n", "process2"); + processes->pids[1] = 0; + notify_other_processes(signo); fprintf(stderr, "[%s] > Releasing resources\n", "process2"); close(read_descriptor); close(write_descriptor); unlink(write_descriptor); - for (; i < 3; i++) { - pid_t pid = processes->pids[i]; - fprintf(stderr, "[%s] Process %d, PID: %d\n", "process2", i, pid); - // Bleh - if (i != 1) { - msgsnd(pid, &msg, sizeof(msg)); - kill(pid, SIGUSR1); - } - } exit(0); } else if (signo == SIGTSTP) { - fprintf(stderr, "[%s] > Closing pipes\n", "process2"); + fprintf(stderr, "[%s] > Close reading pipe\n", "process2"); close(read_descriptor); + notify_other_processes(signo); + fprintf(stderr, "[%s] > Close writing pipe\n", "process2"); close(write_descriptor); raise (SIGSTOP); } else if (signo == SIGCONT) { + fprintf(stderr, "[%s] > Signalling other processes..\n", "process2"); + notify_other_processes(signo); + fprintf(stderr, "[%s] > Opening pipes\n", "process2"); - read_descriptor = open(read_pipe, O_RDONLY); write_descriptor = open(write_pipe, O_WRONLY); + read_descriptor = open(read_pipe, O_RDONLY); } } @@ -147,14 +176,13 @@ int main(void) { * Register memory to share with other processes, and pass current * process id to the array. */ - shmid = shmget(shmkey, sizeof(struct message), IPC_CREAT | 0666); + shmid = shmget(shmkey, sizeof(struct message), 0666); processes = (struct message *)shmat(shmid, NULL, 0); processes->pids[1] = getpid(); fprintf(stderr, "[%s] Shared pid: %d\n", "process2", getpid()); - sleep(1); /** * Register message queue to communicate with other processes */ diff --git a/src/process3.c b/src/process3.c index 54bb658..a012f4c 100644 --- a/src/process3.c +++ b/src/process3.c @@ -2,6 +2,8 @@ /* exit.. */ #include +/* strsignal... */ +#include /* open/read/write/close */ #include @@ -10,6 +12,7 @@ #include #include +#include /** Named pipe used to communicate with process2 */ char * read_pipe = "/tmp/process2pipe"; @@ -50,42 +53,70 @@ int qid_output1; int qid_output2; struct queue_message { - int signo; + long mtype; + int signo[1]; }; +void notify_other_processes(int signo) { + int i = 0; + struct queue_message msg; + msg.signo[0] = signo; + + for (; i < 3; i++) { + pid_t pid = processes->pids[i]; + // Bleh + if (i != 2 && pid != 0) { + msg.mtype = i+1; + fprintf(stderr, "[%s] Sending message of type (%d) with value %d\n", "process3", msg.mtype, msg.signo[0]); + msgsnd(pid, &msg, sizeof(int), 0); + fprintf(stderr, "[%s] Sending signal %s (%d) to PID: %d\n", "process3", strsignal(SIGUSR1), SIGUSR1, pid); + kill(pid, SIGUSR1); + } + } +} + /** * Handler for signals. */ void sig_handler(int signo) { - fprintf(stderr, "[%s] Received %s!\n", "process3", strsignal(signo)); + fprintf(stderr, "[%s] Received !\n", "process3"); if (signo == SIGUSR1) { fprintf(stderr, "[%s] > Notified!\n", "process3"); + struct queue_message msg; + /* Check queues from both other processes */ + if (msgrcv(processes->pids[0], &msg, sizeof(int), 3, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process3", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } + else if (msgrcv(processes->pids[1], &msg, sizeof(int), 3, 0) > 0) { + fprintf(stderr, "[%s] > Notified with value: %s!\n", "process3", strsignal(msg.signo[0])); + raise(msg.signo[0]); + break; + } } else if (signo == SIGTERM) { - int i = 0; - struct queue_message msg; - msg.signo = signo; + fprintf(stderr, "[%s] > Signalling other processes..\n", "process3"); + processes->pids[2] = 0; + notify_other_processes(signo); fprintf(stderr, "[%s] > Releasing resources\n", "process3"); close(read_descriptor); - for (; i < 3; i++) { - pid_t pid = processes->pids[i]; - fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, pid); - // Bleh - if (i != 2) { - msgsnd(pid, &msg, sizeof(msg)); - kill(pid, SIGUSR1); - } - } exit(0); } else if (signo == SIGTSTP) { + fprintf(stderr, "[%s] > Signalling other processes..\n", "process3"); + notify_other_processes(signo); + fprintf(stderr, "[%s] > Closing pipe\n", "process3"); close(read_descriptor); raise (SIGSTOP); } else if (signo == SIGCONT) { + fprintf(stderr, "[%s] > Signalling other processes..\n", "process3"); + notify_other_processes(signo); + fprintf(stderr, "[%s] > Opening pipe\n", "process3"); read_descriptor = open(read_pipe, O_RDONLY); } @@ -124,14 +155,13 @@ int main(void) { * Register memory to share with other processes, and pass current * process id to the array. */ - shmid = shmget(shmkey, sizeof(struct message), IPC_CREAT | 0666); + shmid = shmget(shmkey, sizeof(struct message), 0666); processes = (struct message *)shmat(shmid, NULL, 0); processes->pids[2] = getpid(); fprintf(stderr, "[%s] Shared pid: %d\n", "process3", getpid()); - sleep(1); /** * Register message queue to communicate with other processes */ -- 2.30.2