X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fbdelta%2Fbdelta.h;fp=ccan%2Fbdelta%2Fbdelta.h;h=67ed73d91463a0548190a2f2817d790d9c2e7f9e;hb=d1a8796172f3298d087003c623a049f1177fd060;hp=0000000000000000000000000000000000000000;hpb=aa6b7489835d9bca43049ab6dc7f79d460539345;p=ccan diff --git a/ccan/bdelta/bdelta.h b/ccan/bdelta/bdelta.h new file mode 100644 index 00000000..67ed73d9 --- /dev/null +++ b/ccan/bdelta/bdelta.h @@ -0,0 +1,112 @@ +/* + * Copyright (C) 2011 Joseph Adams + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef CCAN_BDELTA_H +#define CCAN_BDELTA_H + +#include + +typedef enum { + BDELTA_OK = 0, /* Operation succeeded. */ + + BDELTA_MEMORY = 1, /* Memory allocation failed. */ + BDELTA_PATCH_INVALID = 2, /* Patch is malformed. */ + BDELTA_PATCH_MISMATCH = 3, /* Patch applied to wrong original string. */ + + /* Internal error codes. These will never be returned by API functions. */ + BDELTA_INTERNAL_DMAX_EXCEEDED = -10, + BDELTA_INTERNAL_INPUTS_TOO_LARGE = -11, +} BDELTAcode; + +/* + * bdelta_diff - Given two byte strings, generate a "patch" (also a byte string) + * that describes how to transform the old string into the new string. + * + * On success, returns BDELTA_OK, and passes a malloc'd block + * and its size through *patch_out and *patch_size_out. + * + * On failure, returns an error code, and clears *patch_out and *patch_size_out. + * + * Example: + * const char *old = "abcabba"; + * const char *new_ = "cbabac"; + * void *patch; + * size_t patch_size; + * BDELTAcode rc; + * + * rc = bdelta_diff(old, strlen(old), new_, strlen(new_), &patch, &patch_size); + * if (rc != BDELTA_OK) { + * bdelta_perror("bdelta_diff", rc); + * return; + * } + * ... + * free(patch); + */ +BDELTAcode bdelta_diff( + const void *old, size_t old_size, + const void *new_, size_t new_size, + void **patch_out, size_t *patch_size_out +); + +/* + * bdelta_patch - Apply a patch produced by bdelta_diff to the + * old string to recover the new string. + * + * On success, returns BDELTA_OK, and passes a malloc'd block + * and its size through *new_out and *new_size_out. + * + * On failure, returns an error code, and clears *new_out and *new_size_out. + * + * Example: + * const char *old = "abcabba"; + * void *new_; + * size_t new_size; + * BDELTAcode rc; + * + * rc = bdelta_patch(old, strlen(old), patch, patch_size, &new_, &new_size); + * if (rc != BDELTA_OK) { + * bdelta_perror("bdelta_patch", rc); + * return; + * } + * fwrite(new_, 1, new_size, stdout); + * putchar('\n'); + * free(new_); + */ +BDELTAcode bdelta_patch( + const void *old, size_t old_size, + const void *patch, size_t patch_size, + void **new_out, size_t *new_size_out +); + +/* + * bdelta_strerror - Return a string describing a bdelta error code. + */ +const char *bdelta_strerror(BDELTAcode code); + +/* + * bdelta_perror - Print a bdelta error message to stderr. + * + * This function handles @s the same way perror does. + */ +void bdelta_perror(const char *s, BDELTAcode code); + +#endif