1 files changed, 117 insertions, 0 deletions
diff --git a/src/socket.c b/src/socket.c
new file mode 100644
index 0000000..3d0a3ae
--- /dev/null
+++ b/src/socket.c
@@ -0,0 +1,117 @@
+#include <errno.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "runes.h"
+#include "socket.h"
+
+#define MAX_SOCKET_PATH_LEN \
+    (sizeof(struct sockaddr_un) - offsetof(struct sockaddr_un, sun_path))
+
+static void runes_socket_populate_sockaddr(
+    char *path, struct sockaddr_un *addr);
+
+int runes_socket_client_open(char *path)
+{
+    int s;
+    struct sockaddr_un client;
+
+    runes_socket_populate_sockaddr(path, &client);
+
+    s = socket(AF_UNIX, SOCK_STREAM, 0);
+    if (s < 0) {
+        runes_die("couldn't create socket: %s", strerror(errno));
+    }
+
+    if (connect(s, (struct sockaddr*)(&client), sizeof(struct sockaddr_un))) {
+        runes_die(
+            "couldn't connect to socket at %s: %s", path, strerror(errno));
+    }
+
+    return s;
+}
+
+int runes_socket_server_open(char *path)
+{
+    char *dir, *slash;
+    int s;
+    struct sockaddr_un server;
+
+    runes_socket_populate_sockaddr(path, &server);
+
+    dir = strdup(path);
+    slash = strrchr(dir, '/');
+    if (slash == NULL) {
+        runes_die("socket path %s must be an absolute path", path);
+    }
+    *slash = '\0';
+    runes_mkdir_p(dir);
+    free(dir);
+
+    unlink(path);
+
+    s = socket(AF_UNIX, SOCK_STREAM, 0);
+    if (s < 0) {
+        runes_die("couldn't create socket: %s", strerror(errno));
+    }
+
+    if (bind(s, (struct sockaddr*)(&server), sizeof(struct sockaddr_un))) {
+        runes_die(
+            "couldn't bind to socket %s: %s", path, strerror(errno));
+    }
+
+    if (chmod(path, S_IRUSR|S_IWUSR)) {
+        runes_die(
+            "couldn't chmod socket %s: %s", path, strerror(errno));
+    }
+
+    if (listen(s, 5)) {
+        runes_die(
+            "couldn't listen on socket %s: %s", path, strerror(errno));
+    }
+
+    return s;
+}
+
+int runes_socket_server_accept(int ss)
+{
+    struct sockaddr_un client;
+    socklen_t len = sizeof(client);
+    int cs;
+
+    cs = accept(ss, (struct sockaddr*)(&client), &len);
+    if (cs < 0) {
+        runes_die("couldn't accept connection: %s", strerror(errno));
+    }
+
+    return cs;
+}
+
+void runes_socket_client_close(int s)
+{
+    close(s);
+}
+
+void runes_socket_server_close(int s, char *path)
+{
+    close(s);
+    unlink(path);
+}
+
+static void runes_socket_populate_sockaddr(
+    char *path, struct sockaddr_un *addr)
+{
+    size_t name_len = strlen(path) + 1; // including the nul byte
+
+    if (name_len > MAX_SOCKET_PATH_LEN) {
+        runes_die("socket path %s is too long", path);
+    }
+
+    addr->sun_family = AF_UNIX;
+    strncpy(addr->sun_path, path, name_len);
+}