i3/include/libi3.h

/*
 * vim:ts=4:sw=4:expandtab
 */

#ifndef _LIBI3_H
#define _LIBI3_H

/**
 * Try to get the socket path from X11 and return NULL if it doesn’t work.
 *
 * The memory for the socket path is dynamically allocated and has to be
 * free()d by the caller.
 *
 */
char *socket_path_from_x11();

/**
 * Safe-wrapper around malloc which exits if malloc returns NULL (meaning that
 * there is no more memory available)
 *
 */
void *smalloc(size_t size);

/**
 * Safe-wrapper around calloc which exits if malloc returns NULL (meaning that
 * there is no more memory available)
 *
 */
void *scalloc(size_t size);

/**
 * Safe-wrapper around realloc which exits if realloc returns NULL (meaning
 * that there is no more memory available).
 *
 */
void *srealloc(void *ptr, size_t size);

/**
 * Safe-wrapper around strdup which exits if malloc returns NULL (meaning that
 * there is no more memory available)
 *
 */
char *sstrdup(const char *str);

/**
 * Formats a message (payload) of the given size and type and sends it to i3 via
 * the given socket file descriptor.
 *
 * Returns -1 when write() fails, errno will remain.
 * Returns 0 on success.
 *
 */
int ipc_send_message(int sockfd, uint32_t message_size,
                     uint32_t message_type, const uint8_t *payload);

/**
 * Reads a message from the given socket file descriptor and stores its length
 * (reply_length) as well as a pointer to its contents (reply).
 *
 * Returns -1 when read() fails, errno will remain.
 * Returns -2 when the IPC protocol is violated (invalid magic, unexpected
 * message type, EOF instead of a message). Additionally, the error will be
 * printed to stderr.
 * Returns 0 on success.
 *
 */
int ipc_recv_message(int sockfd, uint32_t message_type,
                     uint32_t *reply_length, uint8_t **reply);

#endif