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view array.c @ 56:770737295987
Added pack.c pack.h
libpack-like for opening binary file endianness safe.
author | David Demelier <markand@malikania.fr> |
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date | Tue, 08 Nov 2011 18:26:05 +0100 |
parents | cdae3689f1b6 |
children | 8a8db17c02a4 |
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/* * array.c -- manipulate dynamic arrays * * Copyright (c) 2011, 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 array_grow(struct array *); struct array * array_new(enum array_type type, size_t unit, int length) { struct array *arr; if (unit == 0 || (arr = malloc(sizeof (struct array))) == NULL) return NULL; memset(arr, 0, sizeof (struct array)); arr->type = type; arr->bsize = (length == 0) ? ARRAY_DEFAULT_BSIZE : length; arr->unit = unit; arr->size = OFFSET(arr->bsize); if ((arr->data = malloc(arr->size)) == NULL) { free(arr); return NULL; } return arr; } /* * 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. */ int array_push(struct array *arr, const void *data) { if (array_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 when the index is outof bounds otherwise 0 is returned. */ int array_insert(struct array *arr, const void *data, int index) { if (index > arr->length - 1 || index < 0 || array_grow(arr) < 0) return -1; 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 0; } /* * Append the data to the end of array. */ int array_append(struct array *arr, const void *data) { if (array_grow(arr) < 0) return -1; memcpy((char *) arr->data + OFFSET(arr->length++), data, arr->unit); return 0; } /* * Remove the array's head. */ void array_pop(struct array *arr) { if (arr->length > 0) { memmove((char *) arr->data, (char *) arr->data + OFFSET(1), OFFSET(--arr->length)); memset((char *) arr->data + OFFSET(arr->length), 0, arr->unit); } } /* * Remove the array's tail. */ void array_unqueue(struct array *arr) { if (arr->length > 0) memset((char *) arr->data + OFFSET(--arr->length), 0, arr->unit); } /* * Remove the data at the specified index. Bounds are checked. */ void array_remove(struct array *arr, int index) { if (arr->length > 0 && index >= 0 && index < arr->length) { memmove((char *) arr->data + OFFSET(index), (char *) arr->data + OFFSET(index + 1), OFFSET(arr->length - index - 1)); 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_unref(struct array *arr, const void *data) { void *elm; int i; for (i = 0; i < arr->length; ++i) { elm = ARRAY_INDEX(arr, i); if (memcmp(elm, data, arr->unit) == 0) array_remove(arr, i); } } /* * 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; /* * Only allocate at this time, the user may do not want to use this * function. */ if ((tmp = 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. */ 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(arr->data + OFFSET(i1), o1, arr->unit) == 0; if (!found) return -1; for (i2 = found = 0; !found && i2 < arr->length; ++i2) found = memcmp(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, void (*fn)(void *, void *), 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 then the data is returned. Optional idx argument can be set to * indicate the data position. If the data was not found the function returns * NULL. */ void * array_find(const struct array *arr, int (*fn)(void *, void *), int *ix, void *u) { int st, i; void *data; for (i = st = 0; i < arr->length && st != 1; ++i) st = fn((char *) arr->data + OFFSET(i), u); if (st) { data = (char *) arr->data + OFFSET(--i); if (ix) *ix = i; } else data = NULL; return data; } /* * Erase every bytes and set the length to 0. */ void array_clear(struct array *arr) { 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); if (arr->data) free(arr->data); free(arr); } /* * 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 array_grow(struct array *arr) { if ((arr->size / arr->unit) > (size_t) arr->length) return 0; if (arr->type == ARRAY_AUTO) { if ((arr->data = realloc(arr->data, arr->size + OFFSET(arr->bsize))) == NULL) return -1; arr->size += OFFSET(arr->bsize); } else return -1; return 0; }