Mercurial > code
view array.c @ 147:535f12e0a5af
Add a flag to prevent insertions at out of bounds
author | David Demelier <markand@malikania.fr> |
---|---|
date | Fri, 11 May 2012 20:06:41 +0200 |
parents | e3cf5ac9a5aa |
children | 94847374833b |
line wrap: on
line source
/* * array.c -- manipulate dynamic arrays * * Copyright (c) 2011, 2012, David Demelier <markand@malikania.fr> * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include "array.h" #define OFFSET(x) (arr->unit * (x)) static int grow(struct array *); int array_init(struct array *arr, size_t unit) { if (unit == 0) return -1; arr->unit = unit; arr->size = OFFSET(arr->bsize); /* Set defaults if needed */ arr->bsize = (arr->bsize <= 0) ? ARRAY_DEFAULT_BSIZE : arr->bsize; arr->malloc = (arr->malloc == NULL) ? &malloc : arr->malloc; arr->realloc = (arr->realloc == NULL) ? &realloc : arr->realloc; if ((arr->data = arr->malloc(arr->size)) == NULL) return -1; if (arr->flags & ARRAY_CLEARBITS) memset(arr->data, 0, arr->size); return 0; } /* * Valid options that can be set for an array : * l -> optional array block size of type int * m -> malloc function that must matches void * (*malloc)(size_t) * r -> realloc function that must matches void * (*realloc)(void *, size_t) * f -> array flags of type int */ void array_set(struct array *arr, const char *fmt, ...) { va_list ap; const char *p; va_start(ap, fmt); for (p = fmt; *p != '\0'; ++p) switch (*p) { case 'l': arr->bsize = va_arg(ap, int); break; case 'm': arr->malloc = va_arg(ap, void *(*)(size_t)); break; case 'r': arr->realloc = va_arg(ap, void *(*)(void *, size_t)); break; case 'f': arr->flags = va_arg(ap, int); break; default: break; } } /* * Add to the head of array. NOTE: this may be very slow when adding a lot * of object (about 100000). If you need to add a lot of data please consider * using linked list instead. Returns -1 on failure or 0 on success. */ int array_push(struct array *arr, const void *data) { if (grow(arr) < 0) return -1; memmove((char *)arr->data + arr->unit, arr->data, OFFSET(arr->length++)); memcpy((char *)arr->data, data, arr->unit); return 0; } /* * Insert the data at the specified index. The function returns -1 on * allocation failure or the position of the added element. */ int array_insert(struct array *arr, const void *data, int index) { if (arr->flags & ARRAY_INSERTSAFE) if (index < 0 || index > arr->length) return -1; if (index < 0) return array_push(arr, data); if (index >= arr->length) return array_append(arr, data); /* Good place */ memmove((char *)arr->data + OFFSET(index + 1), (char *)arr->data + OFFSET(index), OFFSET(arr->length++ - index)); memcpy((char *)arr->data + OFFSET(index), data, arr->unit); return index; } /* * Append the data to the end of array. Returns -1 on failure or the position * of the added element. */ int array_append(struct array *arr, const void *data) { if (grow(arr) < 0) return -1; memcpy((char *)arr->data + OFFSET(arr->length++), data, arr->unit); return (arr->length - 1); } /* * Remove the array's head. */ void array_pop(struct array *arr) { array_iremove(arr, 0); } /* * Remove the array's tail. */ void array_unqueue(struct array *arr) { array_iremove(arr, arr->length - 1); } /* * Remove the data at the specified index. Bounds are checked. */ void array_iremove(struct array *arr, int index) { if (arr->length > 0 && index >= 0 && index < arr->length) { if (arr->flags & ARRAY_FASTREMOVE) memmove((char *)arr->data + OFFSET(index), (char *)arr->data + OFFSET(--arr->length), arr->unit); else memmove((char *)arr->data + OFFSET(index), (char *)arr->data + OFFSET(index + 1), OFFSET(arr->length-- - index - 1)); } if (arr->flags & ARRAY_CLEARBITS) memset((char *)arr->data + OFFSET(arr->length), 0, arr->unit); } /* * Remove the object referenced by the `data' argument. Useful when you * don't know the index. */ void array_premove(struct array *arr, const void *data) { void *elm; int i; for (i = 0; i < arr->length; ++i) { elm = (char *)arr->data + OFFSET(i); if (memcmp(elm, data, arr->unit) == 0) { array_iremove(arr, i); break; } } } /* * Swap the two elements referenced by index `i1' and `i2'. This function needs * to allocate data to swap elements thus if the functions fails it returns -1 * otherwise 0 is returned. */ int array_iswap(struct array *arr, int i1, int i2) { void *tmp; /* Out of bounds */ if (i1 >= arr->length || i1 < 0 || i2 >= arr->length || i2 < 0) return -1; if ((tmp = arr->malloc(arr->unit)) == NULL) return -1; memcpy((char *)tmp, (char *)arr->data + OFFSET(i1), arr->unit); memcpy((char *)arr->data + OFFSET(i1), (char *)arr->data + OFFSET(i2), arr->unit); memcpy((char *)arr->data + OFFSET(i2), (char *)tmp, arr->unit); /* * Clear bytes for safety you probably don't want a password or * secure data to be left somewhere in the memory. */ if (arr->flags & ARRAY_CLEARBITS) memset(tmp, 0, arr->unit); free(tmp); return 0; } /* * Swap the two elements referenced by data `o1' and `o2'. This function * may be slow on large arrays since it must travel all the object * to find the indexes. */ int array_pswap(struct array *arr, const void *o1, const void *o2) { int found, i1, i2; for (i1 = found = 0; !found && i1 < arr->length; ++i1) found = memcmp((char *)arr->data + OFFSET(i1), o1, arr->unit) == 0; if (!found) return -1; for (i2 = found = 0; !found && i2 < arr->length; ++i2) found = memcmp((char *)arr->data + OFFSET(i2), o2, arr->unit) == 0; if (!found) return -1; return array_iswap(arr, --i1, --i2); } /* * Apply the function `fn' on each object and give the optional `udata' * argument to the function too. */ void array_map(const struct array *arr, array_map_t fn, void *udata) { int i; for (i = 0; i < arr->length; ++i) fn((char *)arr->data + OFFSET(i), udata); } /* * Compare each object with the user supplied function. If the `fn' function * returns 1, 1 is returned and dst points to the correct object, dst should * be a pointer to a pointer of object, like (int **) for a array of int. */ int array_find(const struct array *arr, array_cmp_t fn, void *dst, void *u) { int st, i; for (i = st = 0; i < arr->length && st != 1; ++i) st = fn((char *)arr->data + OFFSET(i), u); if (st && dst) *(char **)dst = (char *)arr->data + OFFSET(i - 1); return (st) ? i - 1 : -1; } void * array_first(const struct array *arr) { return arr->data; } void * array_last(const struct array *arr) { if (arr->length == 0) return array_first(arr); return (char *)arr->data + OFFSET(arr->length - 1); } void * array_index(const struct array *arr, int idx) { if (idx < 0) return array_first(arr); if (idx >= arr->length) return array_last(arr); return (char *)arr->data + OFFSET(idx); } /* * Erase every bytes and set the length to 0. */ void array_clear(struct array *arr) { if (arr->flags & ARRAY_CLEARBITS) memset(arr->data, 0, arr->size); arr->length = 0; } /* * Same as array_clear except it also free the array object. */ void array_free(struct array *arr) { array_clear(arr); free(arr->data); arr->data = NULL; arr->size = 0; } /* * Increate the array storage when it is full. If the buffer is fixed size * it returns -1 on full buffer otherwise 0 is returned if allocation * succeeded. */ static int grow(struct array *arr) { if ((arr->size / arr->unit) > (size_t)arr->length) return 0; if (!(arr->flags & ARRAY_FIXED)) { if ((arr->data = arr->realloc(arr->data, arr->size + OFFSET(arr->bsize))) == NULL) { arr->size = arr->length = 0; return -1; } arr->size += OFFSET(arr->bsize); } else return -1; return 0; }