Basic IPC stuff

src/common.h

@@ -0,0 +1,48 @@
+#ifndef _SFXD_COMMON_H_
+#define _SFXD_COMMON_H_
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define BUFFER_SIZE 8192
+#define DAEMON_SOCKET_PATH "/tmp/sfxd-ipc"
+#define CLIENT_SOCKET_PATH "/tmp/sfxd-client-%ld"
+
+#define PANIC_FMT(FMT, ...) _panic(__LINE__, __FILE__, errno, FMT, __VA_ARGS__)
+#define PANIC(TXT) _panic(__LINE__, __FILE__, errno, TXT)
+#define EXPECT(CODE, CONDITION) { \
+  ssize_t __res = (CODE); \
+  if (!(__res CONDITION)) \
+    PANIC_FMT("%s failed condition: %zd %s", #CODE, __res, #CONDITION); \
+}
+
+static inline void _panic(int line, const char *filename, int _errno, const char *fmt, ...) {
+  fprintf(stderr, "Panic at %s:%d\nMessage: ", filename, line);
+  va_list args;
+  va_start(args, fmt);
+  vfprintf(stderr, fmt, args);
+  va_end(args);
+
+  fprintf(stderr, "\nerrno: %d (%s)\n", _errno, strerror(_errno));
+
+  exit(EXIT_FAILURE);
+}
+
+static inline uint32_t adler32(const void *buf, size_t buflength) {
+  const uint8_t *buffer = (const uint8_t*)buf;
+
+  uint32_t s1 = 1;
+  uint32_t s2 = 0;
+
+  for (size_t n = 0; n < buflength; n++) {
+    s1 = (s1 + buffer[n]) % 65521;
+    s2 = (s2 + s1) % 65521;
+  }
+  return (s2 << 16) | s1;
+}
+
+#endif

src/sfxc.c

@@ -1,6 +1,40 @@
+#include "common.h"
 #include <stdio.h>
-#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
 
-int main(void) {
-  printf("Hi!\n");
+int main(int argc, char **argv) {
+  struct sockaddr_un sa_server, sa_client;
+  int sock_fd;
+  static char buffer[BUFFER_SIZE];
+
+  EXPECT(sock_fd = socket(AF_UNIX, SOCK_DGRAM, 0), > 0);
+
+  memset(&sa_server, 0, sizeof(sa_server));
+  memset(&sa_client, 0, sizeof(sa_client));
+
+  sa_server.sun_family = sa_client.sun_family = AF_UNIX;
+  snprintf(sa_client.sun_path, sizeof(sa_client.sun_path), CLIENT_SOCKET_PATH, (long)getpid());
+  strncpy(sa_server.sun_path, DAEMON_SOCKET_PATH, sizeof(sa_server.sun_path) - 1);
+
+  EXPECT(bind(sock_fd, (struct sockaddr *)&sa_client, sizeof(struct sockaddr_un)), == 0);
+
+  for (int i = 1; i < argc; i++) {
+    strncat(buffer, argv[1], BUFFER_SIZE - strlen(buffer) - 1);
+    if (i != argc - 1) {
+      strncat(buffer, " ", BUFFER_SIZE - strlen(buffer) - 1);
+    }
+  }
+
+  EXPECT(sendto(sock_fd, buffer, strlen(buffer), 0, (struct sockaddr *)&sa_server, sizeof(sa_server)), == strlen(buffer));
+  int data_len;
+  while ((data_len = recv(sock_fd, buffer, BUFFER_SIZE, 0)) > 0) {
+    printf("%.*s", data_len, buffer);
+  }
+
+  unlink(sa_client.sun_path);
+  exit(EXIT_SUCCESS);
 }

src/sfxd.c

@@ -1,6 +1,77 @@
+#include "common.h"
+#include <stdbool.h>
 #include <stdio.h>
-#include <math.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
 
-int main(void) {
-  printf("Hi!\n");
+struct msg_target {
+  FILE *file_handle;
+  int sock_fd;
+  struct sockaddr *sock_addr;
+  ssize_t sock_addr_size;
+};
+
+ssize_t send_data(struct msg_target tgt, const void *data, size_t len);
+void execute_command(struct msg_target tgt, const char *command, const char *params);
+
+int main(int argc, char **argv) {
+
+  struct sockaddr_un sa_server, sa_client;
+  int sock_fd;
+  static char buffer[BUFFER_SIZE];
+
+  char *sock_path = DAEMON_SOCKET_PATH;
+
+  EXPECT(sock_fd = socket(AF_UNIX, SOCK_DGRAM, 0), > 0);
+
+  memset(&sa_server, 0, sizeof(sa_server));
+  memset(&sa_client, 0, sizeof(sa_client));
+
+  sa_server.sun_family = AF_UNIX;
+  strncpy(sa_server.sun_path, sock_path, sizeof(sa_server.sun_path) - 1);
+
+  unlink(sa_server.sun_path);
+  EXPECT(bind(sock_fd, (struct sockaddr *)&sa_server, sizeof(struct sockaddr_un)), >= 0);
+
+  ssize_t data_len;
+  socklen_t sl_client = sizeof(sa_client);
+  while ((data_len = recvfrom(sock_fd, buffer, sizeof(buffer) - 1, 0, (struct sockaddr *)&sa_client, &sl_client)) != -1) {
+    buffer[data_len] = '\0';
+    struct sockaddr_un *sau_client = &sa_client;
+    char *command = buffer;
+    char *params = strchr(buffer, ' ');
+    if (params != NULL) {
+      *params = '\0';
+      params++;
+    }
+    execute_command((struct msg_target) { 0, sock_fd, (struct sockaddr *)&sa_client, sl_client }, command, params);
+    EXPECT(sendto(sock_fd, "OK\n", 4, 0, (struct sockaddr *)&sa_client, sl_client), == 4);
+    EXPECT(sendto(sock_fd, "", 0, 0, (struct sockaddr *)&sa_client, sl_client), == 0);
+    sl_client = sizeof(sa_client);
+  }
+
+  unlink(sa_server.sun_path);
+}
+
+ssize_t send_data(struct msg_target tgt, const void *data, size_t len) {
+  ssize_t written;
+  if (tgt.file_handle) {
+    if ((written = fwrite(data, 1, len, tgt.file_handle)) != len) {
+      PANIC_FMT("fwrite(ptr=%p, size=%zd, nmemb=%zd, stream=%p) -> %zd",
+          data, 1, len, tgt.file_handle, written);
+    }
+  } else {
+    if ((written = sendto(tgt.sock_fd, data, len, 0, tgt.sock_addr, tgt.sock_addr_size)) != len) {
+      PANIC_FMT("sendto(socket=%d, message=%p, length=%zd, flags=%d, dest_addr=%p, dest_len=%zd) -> %zd",
+          tgt.sock_fd, data, len, 0, tgt.sock_addr, tgt.sock_addr_size, written);
+    }
+  }
+
+  return written;
+}
+
+void execute_command(struct msg_target tgt, const char *command, const char *params) {
+  send_data(tgt, "WAAAAAAAAAAAAAA\n", 16);
 }