/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2019-2020 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project * by Aaron LI <aly@aaronly.me> * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name of The DragonFly Project nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific, prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef UTILS_H_ #define UTILS_H_ #include <ctype.h> #include <err.h> #include <errno.h> #include <math.h> #include <stdbool.h> #include <stddef.h> #include <string.h> #ifndef nitems #define nitems(x) (sizeof(x) / sizeof((x)[0])) #endif /* * Return true if string $s1 starts with the string $s2. */ static inline bool string_startswith(const char *s1, const char *s2) { return (s1 && s2 && strncmp(s1, s2, strlen(s2)) == 0); } /* * Count the number of character $ch in string $s. */ static inline size_t count_char(const char *s, int ch) { size_t count = 0; for ( ; *s; s++) { if (*s == ch) count++; } return count; } /* * Trim the leading whitespaces of the given string $s * and return the trimed string. */ static inline char * triml(char *s) { while (isspace((unsigned char)*s)) s++; return s; } /* * Trim the trailing whitespaces of the given string $s * and return the trimed string. */ static inline char * trimr(char *s) { size_t l = strlen(s); while (l > 0 && isspace((unsigned char) s[l-1])) l--; s[l] = '\0'; return s; } /* * Swap the values of two integers. */ static inline void swap(int *a, int *b) { int tmp = *a; *a = *b; *b = tmp; } /* * Divide integer $x by integer $y, rounding towards minus infinity. */ static inline int div_floor(int x, int y) { int q = x / y; int r = x % y; if ((r != 0) && ((r < 0) != (y < 0))) q--; return q; } /* * Calculate the remainder of $x divided by $y; the result has the same * sign as $y. * Ref: Sec.(1.7), Eq.(1.17) */ static inline int mod(int x, int y) { return x - y * div_floor(x, y); } static inline double mod_f(double x, double y) { return x - y * floor(x / y); } /* * Return the value of ($x % $y) with $y instead of 0, i.e., with value * range being [1, $y]. */ static inline int mod1(int x, int y) { return y + mod(x, -y); } /* * Calculate the interval modulus of $x, i.e., shifted into the range * [$a, $b). Return $x if $a = $b. * Ref: Sec.(1.7), Eq.(1.24) */ static inline int mod3(int x, int a, int b) { if (a == b) return x; else return a + mod(x - a, b - a); } static inline double mod3_f(double x, double a, double b) { static const double eps = 1e-6; if (fabs(a - b) < eps) return x; else return a + mod_f(x - a, b - a); } /* * Calculate the sine value of degree $deg. */ static inline double sin_deg(double deg) { return sin(M_PI * deg / 180.0); } /* * Calculate the cosine value of degree $deg. */ static inline double cos_deg(double deg) { return cos(M_PI * deg / 180.0); } /* * Calculate the tangent value of degree $deg. */ static inline double tan_deg(double deg) { return tan(M_PI * deg / 180.0); } /* * Calculate the arc sine value (in degrees) of $x. */ static inline double arcsin_deg(double x) { return asin(x) * 180.0 / M_PI; } /* * Calculate the arc cosine value (in degrees) of $x. */ static inline double arccos_deg(double x) { return acos(x) * 180.0 / M_PI; } /* * Calculate the arc tangent value (in degrees from 0 to 360) of $y / $x. * Error if $x and $y are both zero. */ static inline double arctan_deg(double y, double x) { errno = 0; double v = atan2(y, x); if (errno == EDOM) errx(10, "%s(%g, %g) invalid!", __func__, y, x); return mod_f(v * 180.0 / M_PI, 360); } /* * Convert angle in (degree, arcminute, arcsecond) to degree. */ static inline double angle2deg(int deg, int min, double sec) { return deg + min/60.0 + sec/3600.0; } double poly(double x, const double *coefs, size_t n); double invert_angular(double (*f)(double), double y, double a, double b); void * xmalloc(size_t size); void * xcalloc(size_t number, size_t size); void * xrealloc(void *ptr, size_t size); char * xstrdup(const char *str); struct node; struct node * list_newnode(char *name, void *data); struct node * list_addfront(struct node *listp, struct node *newp); bool list_lookup(struct node *listp, const char *name, int (*cmp)(const char *, const char *), void **data_out); void list_freeall(struct node *listp, void (*free_name)(void *), void (*free_data)(void *)); #endif
