misc

Signed-off-by: Mattias Andrée <maandree@operamail.com>

3 files changed, 91 insertions, 51 deletions

diff --git a/Makefile b/Makefile
index fa12410..94b203e 100644
--- a/Makefile
+++ b/Makefile
@@ -5,15 +5,15 @@ all: bus
 
 bus: bin/bus
 
-bin/bus: obj/cmdline.o
+bin/bus: obj/cmdline.o obj/bus.o
 	@echo CC -o $@
 	@mkdir -p bin
 	@${CC} -o $@ $^ ${LDFLAGS}
 
-obj/%.o: src/%.c
+obj/%.o: src/%.c src/*.h
 	@echo CC -c $<
 	@mkdir -p obj
-	@${CC} -c -o $@ ${CPPFLAGS} ${CFLAGS} $<
+	@${CC} -Wall -Wextra -pedantic -c -o $@ ${CPPFLAGS} ${CFLAGS} $<
 
 clean:
 	@echo cleaning
diff --git a/src/bus.c b/src/bus.c
index 7f05560..5965a14 100644
--- a/src/bus.c
+++ b/src/bus.c
@@ -180,8 +180,8 @@ create_semaphores(bus_t *bus)
 
 fail:
 	saved_errno = errno;
-	if ((id != -1) && (semctl(id, 0, IPC_RMID) == -1))
-		perror(argv0);
+	if (id != -1)
+		semctl(id, 0, IPC_RMID);
 	free(values.array);
 	errno = saved_errno;
 	return -1;
@@ -221,8 +221,8 @@ create_shared_memory(bus_t *bus)
 
 fail:
 	saved_errno = errno;
-	if ((id != -1) && (shmctl(id, IPC_RMID, &_info) == -1))
-		perror(argv0);
+	if (id != -1)
+		shmctl(id, IPC_RMID, &_info);
 	errno = saved_errno;
 	return -1;
 }
@@ -253,7 +253,7 @@ remove_shared_memory(const bus_t *bus)
 {
 	struct shmid_ds _info;
 	int id = shmget(bus->key_shm, BUS_MEMORY_SIZE, 0600);
-	return ((id == -1) || (shmctl(sem_id, IPC_RMID, &_info) == -1)) ? -1 : 0;
+	return ((id == -1) || (shmctl(id, IPC_RMID, &_info) == -1)) ? -1 : 0;
 }
 
 
@@ -302,7 +302,7 @@ write_semaphore(const bus_t *bus, unsigned short semaphore, int value)
  * @return         0 on success, -1 on error
  */
 static int
-open_shared_memory(const bus_t *bus, int flags)
+open_shared_memory(bus_t *bus, int flags)
 {
 	int id;
 	void *address;
@@ -310,7 +310,7 @@ open_shared_memory(const bus_t *bus, int flags)
 	address = shmat(id, NULL, (flags & BUS_RDONLY) ? SHM_RDONLY : 0);
 	if ((address == (void *)-1) || !address)
 		goto fail;
-	this->message = (char *)address;
+	bus->message = (char *)address;
 	return 0;
 fail:
 	return -1;
@@ -324,10 +324,10 @@ fail:
  * @return       0 on success, -1 on error
  */
 static int
-close_shared_memory(const bus_t *bus)
+close_shared_memory(bus_t *bus)
 {
-	t(shmdt(this->message));
-	this->message = NULL;
+	t(shmdt(bus->message));
+	bus->message = NULL;
 	return 0;
 fail:
 	return -1;
@@ -356,9 +356,11 @@ bus_create(const char *file, int flags)
 
 	srand((unsigned int)time(NULL) + (unsigned int)rand());
 
+	/* TODO */ (void) file; (void) flags;
+
 	t(create_semaphores(&bus));
 	t(create_shared_memory(&bus));
-	return NULL; /* TODO */
+	return NULL;
 
 fail:
 	saved_errno = errno;
@@ -417,12 +419,27 @@ fail:
 int
 bus_open(bus_t *bus, const char *file, int flags)
 {
+	int saved_errno;
+	char *line = NULL;
+	size_t len = 0;
+	FILE *f;
+
 	bus->sem_id = -1;
 	bus->key_sem = -1;
 	bus->key_shm = -1;
 	bus->message = NULL;
 
-	/* TODO */
+	f = fopen(file, "r");
+
+	t(getline(&line, &len, f));
+	t(bus->key_sem = (key_t)atoll(line));
+	free(line), line = NULL, len = 0;
+
+	t(getline(&line, &len, f));
+	t(bus->key_shm = (key_t)atoll(line));
+	free(line), line = NULL;
+
+	fclose(f);
 
 	if (flags >= 0) {
 		t(open_semaphores(bus));
@@ -430,6 +447,9 @@ bus_open(bus_t *bus, const char *file, int flags)
 	}
 	return 0;
 fail:
+	saved_errno = errno;
+	free(line);
+	errno = saved_errno;
 	return -1;
 }
 
@@ -444,9 +464,9 @@ int
 bus_close(bus_t *bus)
 {
 	bus->sem_id = -1;
-	if (bus->address)
+	if (bus->message)
 		t(close_shared_memory(bus));
-	bus->address = NULL;
+	bus->message = NULL;
 	return 0;
 fail:
 	return -1;
@@ -466,7 +486,7 @@ bus_write(const bus_t *bus, const char *message)
 {
 	t(acquire_semaphore(bus, X, SEM_UNDO));
 	t(zero_semaphore(bus, W));
-	t(write_shared_memory(bus, message));
+	write_shared_memory(bus, message);
 	t(write_semaphore(bus, Q, 0));
 	t(zero_semaphore(bus, S));
 	t(release_semaphore(bus, X, SEM_UNDO));
diff --git a/src/cmdline.c b/src/cmdline.c
index d3b2a07..fbee2d6 100644
--- a/src/cmdline.c
+++ b/src/cmdline.c
@@ -21,48 +21,42 @@
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
 #include "bus.h"
 
 
+
 /**
  * Statement wrapper that goes to `fail` on failure
  */
 #define t(inst)  if ((inst) == -1)  goto fail
 
 
-char *argv0;
-static const char *command;
-
-
-static int
-get_keys(void)
-{
-	int saved_errno;
-	char *line;
-	size_t len;
 
-	line = NULL, len = 0;
-	t(getline(&line, &len, stdin));
-	t(key_sem = (key_t)atoll(line));
-	free(line);
-
-	line = NULL, len = 0;
-	t(getline(&line, &len, stdin));
-	t(key_shm = (key_t)atoll(line));
-	free(line);
+/**
+ * The name of the process
+ */
+char *argv0;
 
-	return 0;
+/**
+ * The command to spawn when a message is received
+ */
+static const char *command;
 
-fail:
-	saved_errno = errno;
-	free(line);
-	errno = saved_errno;
-	return -1;
-}
 
 
+/**
+ * Spawn a command because a message has been received
+ * 
+ * @param   message    The received message
+ * @param   user_data  Not used
+ * @return             1 (continue listening) on success, -1 on error
+ */
 static int
-spawn_continue(const char *message)
+spawn_continue(const char *message, void *user_data)
 {
 	pid_t pid = fork();
 	if (pid)
@@ -71,11 +65,19 @@ spawn_continue(const char *message)
 	execlp("sh", "sh", "-c", command, NULL);
 	perror(argv0);
 	exit(1);
+	(void) user_data;
 }
 
 
+/**
+ * Spawn a command because a message has been received
+ * 
+ * @param   message    The received message
+ * @param   user_data  Not used
+ * @return             0 (stop listening) on success, -1 on error
+ */
 static int
-spawn_break(const char *message)
+spawn_break(const char *message, void *user_data)
 {
 	pid_t pid = fork();
 	if (pid)
@@ -84,9 +86,24 @@ spawn_break(const char *message)
 	execlp("sh", "sh", "-c", command, NULL);
 	perror(argv0);
 	exit(1);
+	(void) user_data;
 }
 
 
+
+/**
+ * Main function of the command line interface for the bus system
+ * 
+ * @param   argc  The number of elements in `argv`
+ * @param   argv  The command. Valid commands:
+ *                  <argv0> create [<path>]             # create a bus
+ *                  <argv0> remove <path>               # remove a bus
+ *                  <argv0> listen <path> <command>     # listen for new messages
+ *                  <argv0> wait <path> <command>       # listen for one new message
+ *                  <argv0> broadcast <path> <message>  # broadcast a message
+ *                <command> will be spawned with $arg set to the message
+ * @return        0 on sucess, 1 on error, 2 on invalid command
+ */
 int
 main(int argc, char *argv[])
 {
@@ -94,32 +111,38 @@ main(int argc, char *argv[])
 
 	argv0 = *argv;
 
+	/* Create a new bus with selected name. */
 	if ((argc == 3) && !strcmp(argv[1], "create")) {
 		t(bus_create(argv[2], 0) ? 0 : -1);
 
+	/* Create a new bus with random name. */
 	} else if ((argc == 2) && !strcmp(argv[1], "create")) {
-		char *file = bus_create(NULL, 0);
+		const char *file = bus_create(NULL, 0);
 		t(file ? 0 : -1);
 		printf("%s\n", file);
 
+	/* Remove a bus. */
 	} else if ((argc == 3) && !strcmp(argv[1], "remove")) {
 		t(bus_unlink(argv[2]));
 
+	/* Listen on a bus in a loop. */
 	} else if ((argc == 4) && !strcmp(argv[1], "listen")) {
 		command = argv[3];
 		t(bus_open(&bus, argv[2], BUS_RDONLY));
 		t(bus_read(&bus, spawn_continue, NULL));
 		t(bus_close(&bus));
 
+	/* Listen on a bus for one message. */
 	} else if ((argc == 4) && !strcmp(argv[1], "wait")) {
 		command = argv[3];
 		t(bus_open(&bus, argv[2], BUS_RDONLY));
 		t(bus_read(&bus, spawn_break, NULL));
 		t(bus_close(&bus));
 
+	/* Broadcast a message on a bus. */
 	} else if ((argc == 4) && !strcmp(argv[1], "broadcast")) {
 		t(bus_open(&bus, argv[2], BUS_WRONLY));
-		t(bus_write(&bus, argv[3]))
+		t(bus_write(&bus, argv[3]));
 		t(bus_close(&bus));
 
 	} else
@@ -132,6 +155,3 @@ fail:
 	return 1;
 }
 
-
-#undef t
-