i3/include/util.h

/*
 * vim:ts=4:sw=4:expandtab
 *
 * i3 - an improved dynamic tiling window manager
 * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
 *
 * util.c: Utility functions, which can be useful everywhere within i3 (see
 *         also libi3).
 *
 */
#pragma once

#include <config.h>

#include <err.h>

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

#define NODES_FOREACH_REVERSE(head)                                            \
    for (Con *child = (Con *)-1; (child == (Con *)-1) && ((child = 0), true);) \
        TAILQ_FOREACH_REVERSE (child, &((head)->nodes_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 {                \
        free(pointer);  \
        pointer = NULL; \
    } while (0)

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

#define SWAP(first, second, type) \
    do {                          \
        type tmp_SWAP = first;    \
        first = second;           \
        second = tmp_SWAP;        \
    } while (0)

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);
Rect rect_sub(Rect a, Rect b);
bool rect_equals(Rect a, Rect b);
Rect rect_sanitize_dimensions(Rect rect);

/**
 * Returns true if the name consists of only digits.
 *
 */
__attribute__((pure)) bool name_is_digits(const char *name);

/**
 * Set 'out' to the layout_t value for the given layout. The function
 * returns true on success or false if the passed string is not a valid
 * layout name.
 *
 */
bool layout_from_name(const char *layout_str, layout_t *out);

/**
 * Parses the workspace name as a number. Returns -1 if the workspace should be
 * interpreted as a "named workspace".
 *
 */
int ws_name_to_number(const char *name);

/**
 * 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);

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

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

/**
 * Escapes the given string if a pango font is currently used.
 * If the string has to be escaped, the input string will be free'd.
 *
 */
char *pango_escape_markup(char *input);

/**
 * Starts an i3-nagbar instance with the given parameters. Takes care of
 * handling SIGCHLD and killing i3-nagbar when i3 exits.
 *
 * The resulting PID will be stored in *nagbar_pid and can be used with
 * kill_nagbar() to kill the bar later on.
 *
 */
void start_nagbar(pid_t *nagbar_pid, char *argv[]);

/**
 * Kills the i3-nagbar process, if nagbar_pid != -1.
 *
 * If wait_for_it is set (restarting i3), this function will waitpid(),
 * otherwise, ev is assumed to handle it (reloading).
 *
 */
void kill_nagbar(pid_t nagbar_pid, bool wait_for_it);

/**
 * Converts a string into a long using strtol().
 * This is a convenience wrapper checking the parsing result. It returns true
 * if the number could be parsed.
 */
bool parse_long(const char *str, long *out, int base);

/**
 * Slurp reads path in its entirety into buf, returning the length of the file
 * or -1 if the file could not be read. buf is set to a buffer of appropriate
 * size, or NULL if -1 is returned.
 *
 */
ssize_t slurp(const char *path, char **buf);

/**
 * Convert a direction to its corresponding orientation.
 *
 */
orientation_t orientation_from_direction(direction_t direction);

/**
 * Convert a direction to its corresponding position.
 *
 */
position_t position_from_direction(direction_t direction);

/**
 * Convert orientation and position to the corresponding direction.
 *
 */
direction_t direction_from_orientation_position(orientation_t orientation, position_t position);

/**
 * Converts direction to a string representation.
 *
 */
const char *direction_to_string(direction_t direction);

/**
 * Converts position to a string representation.
 *
 */
const char *position_to_string(position_t position);