i3/include/util.h

/*
 * vim:ts=8:expandtab
 *
 * i3 - an improved dynamic tiling window manager
 *
 * © 2009 Michael Stapelberg and contributors
 *
 * See file LICENSE for license information.
 *
 */
#include <err.h>

#include "data.h"

#ifndef _UTIL_H
#define _UTIL_H

#define die(...) errx(EXIT_FAILURE, __VA_ARGS__);
#define exit_if_null(pointer, ...) { if (pointer == NULL) die(__VA_ARGS__); }
#define STARTS_WITH(string, needle) (strncasecmp(string, needle, strlen(needle)) == 0)
#define CIRCLEQ_NEXT_OR_NULL(head, elm, field) (CIRCLEQ_NEXT(elm, field) != CIRCLEQ_END(head) ? \
                                                CIRCLEQ_NEXT(elm, field) : NULL)
#define CIRCLEQ_PREV_OR_NULL(head, elm, field) (CIRCLEQ_PREV(elm, field) != CIRCLEQ_END(head) ? \
                                                CIRCLEQ_PREV(elm, field) : NULL)
#define FOR_TABLE(workspace) \
                        for (int cols = 0; cols < (workspace)->cols; cols++) \
                                for (int rows = 0; rows < (workspace)->rows; rows++)

#define NODES_FOREACH(head) \
    for (Con *child = (Con*)-1; (child == (Con*)-1) && ((child = 0), true);) \
        TAILQ_FOREACH(child, &((head)->nodes_head), nodes)

/* greps the ->nodes of the given head and returns the first node that matches the given condition */
#define GREP_FIRST(dest, head, condition) \
    NODES_FOREACH(head) { \
        if (!(condition)) \
            continue; \
        \
        (dest) = child; \
        break; \
    }

#define FREE(pointer) do { \
        if (pointer != NULL) { \
                free(pointer); \
                pointer = NULL; \
        } \
} \
while (0)

#define CALL(obj, member, ...) obj->member(obj, ## __VA_ARGS__)

int min(int a, int b);
int max(int a, int b);
bool rect_contains(Rect rect, uint32_t x, uint32_t y);
Rect rect_add(Rect a, Rect b);

/**
 * Updates *destination with new_value and returns true if it was changed or false
 * if it was the same
 *
 */
bool update_if_necessary(uint32_t *destination, const uint32_t new_value);

/**
 * 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);

/**
 * Starts the given application by passing it through a shell. We use double
 * fork to avoid zombie processes. As the started application’s parent exits
 * (immediately), the application is reparented to init (process-id 1), which
 * correctly handles childs, so we don’t have to do it :-).
 *
 * The shell is determined by looking for the SHELL environment variable. If
 * it does not exist, /bin/sh is used.
 *
 */
void start_application(const char *command);

/**
 * exec()s an i3 utility, for example the config file migration script or
 * i3-nagbar. This function first searches $PATH for the given utility named,
 * then falls back to the dirname() of the i3 executable path and then falls
 * back to the dirname() of the target of /proc/self/exe (on linux).
 *
 * This function should be called after fork()ing.
 *
 * The first argument of the given argv vector will be overwritten with the
 * executable name, so pass NULL.
 *
 * If the utility cannot be found in any of these locations, it exits with
 * return code 2.
 *
 */
void exec_i3_utility(char *name, char *argv[]);

/**
 * Checks a generic cookie for errors and quits with the given message if
 * there was an error.
 *
 */
void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie,
                 char *err_message);

/**
 * Converts the given string to UCS-2 big endian for use with
 * xcb_image_text_16(). The amount of real glyphs is stored in real_strlen, a
 * buffer containing the UCS-2 encoded string (16 bit per glyph) is
 * returned. It has to be freed when done.
 *
 */
char *convert_utf8_to_ucs2(char *input, int *real_strlen);

/**
 * This function resolves ~ in pathnames.
 * It may resolve wildcards in the first part of the path, but if no match
 * or multiple matches are found, it just returns a copy of path as given.
 *
 */
char *resolve_tilde(const char *path);

/**
 * Checks if the given path exists by calling stat().
 *
 */
bool path_exists(const char *path);


/**
 * Returns the name of a temporary file with the specified prefix.
 *
 */
char *get_process_filename(const char *prefix);

/**
 * Restart i3 in-place
 * appends -a to argument list to disable autostart
 *
 */
void i3_restart(bool forget_layout);

#endif