ipc: Add ipc support to imv

1 files changed, 131 insertions, 0 deletions

diff --git a/src/ipc.c b/src/ipc.c
new file mode 100644
index 0000000..745433f
--- /dev/null
+++ b/src/ipc.c
@@ -0,0 +1,131 @@
+#include "ipc.h"
+
+#include <ctype.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+struct imv_ipc {
+  int fd;
+  imv_ipc_callback callback;
+  void *data;
+};
+
+struct connection {
+  struct imv_ipc *ipc;
+  int fd;
+};
+
+static void get_ipc_filename(char *buf, size_t len)
+{
+  const char *base = getenv("XDG_RUNTIME_DIR");
+  if (!base) {
+    base = "/tmp";
+  }
+  snprintf(buf, len, "%s/imv-%d.sock", base, getpid());
+}
+
+void *wait_for_commands(void* void_conn)
+{
+  struct connection *conn = void_conn;
+
+  while (1) {
+    char buf[1024];
+    ssize_t len = recv(conn->fd, buf, sizeof buf - 1, 0);
+    if (len == -1) {
+      break;
+    }
+
+    buf[len] = 0;
+    while (len > 0 && isspace(buf[len-1])) {
+      buf[len-1] = 0;
+      --len;
+    }
+
+    if (conn->ipc->callback) {
+      conn->ipc->callback(buf, conn->ipc->data);
+    }
+  }
+
+  close(conn->fd);
+  free(conn);
+  return NULL;
+}
+
+void *wait_for_connections(void* void_ipc)
+{
+  struct imv_ipc *ipc = void_ipc;
+  (void)ipc;
+
+  while (1) {
+    int client = accept(ipc->fd, NULL, NULL);
+    if (client == -1) {
+      break;
+    }
+    struct connection *conn = calloc(1, sizeof *conn);
+    conn->ipc = ipc;
+    conn->fd = client;
+
+    pthread_t thread;
+    pthread_create(&thread, NULL, wait_for_commands, conn);
+    pthread_detach(thread);
+  }
+  return NULL;
+}
+
+struct imv_ipc *imv_ipc_create(void)
+{
+  int sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
+  if (sockfd < 0) {
+    return NULL;
+  }
+
+  struct sockaddr_un desc = {
+    .sun_family = AF_UNIX
+  };
+  get_ipc_filename(desc.sun_path, sizeof desc.sun_path);
+
+  unlink(desc.sun_path);
+
+  if (bind(sockfd, (struct sockaddr*)&desc, sizeof desc) == -1) {
+    return NULL;
+  }
+
+  if (listen(sockfd, 5) == -1) {
+    close(sockfd);
+    return NULL;
+  }
+
+  struct imv_ipc *ipc = calloc(1, sizeof *ipc);
+  ipc->fd = sockfd;
+
+  pthread_t thread;
+  pthread_create(&thread, NULL, wait_for_connections, ipc);
+  pthread_detach(thread);
+  return ipc;
+}
+
+void imv_ipc_free(struct imv_ipc *ipc)
+{
+  if (!ipc) {
+    return;
+  }
+
+  char ipc_filename[1024];
+  get_ipc_filename(ipc_filename, sizeof ipc_filename);
+  unlink(ipc_filename);
+  close(ipc->fd);
+
+  free(ipc);
+}
+
+void imv_ipc_set_command_callback(struct imv_ipc *ipc,
+    imv_ipc_callback callback, void *data)
+{
+  ipc->callback = callback;
+  ipc->data = data;
+}
+