Fast*er* string comparison
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LEAKS | ||
Makefile | ||
README | ||
streecmp.a | ||
streecmp.c | ||
streecmp.h | ||
test.c |
+==============+ | streecmp | +==============+ Fast*er* string comparison - an alternative to thousands of strcmp calls This is an O(n) solution - n being the length of the string to be checked. A plus is that this method will stay O(n) *no matter the length of the string nor the number of strings to be checked against*. Potential minuses might be the additional memory needed to store the trie data structure or the computational time required to generate the tree before utilizing it. Therefore, users are advised to use a secure, fast hashmap instead of streecmp. streecmp is only applied to specific scenarios where a rather simple or fast solution for string comparison is required so the project moves on. RES: en.wikipedia.org/wiki/Trie RES: en.wikipedia.org/wiki/Suffix_tree RES: en.wikipedia.org/wiki/Radix_tree RES: facweb.cs.depaul.edu/mobasher/classes/csc575/Suffix_Trees/index.html TECHNICALS struct nod * data structure that represents a node of the tree void frenod(struct nod *nod) * free memory of node and all of its children struct nod *allocnod(void) * allocate memory for a node and its pool size for character hashmap * returns: poiner to said node or NULL if function fails struct nod *mknod(struct nod *nod, int loc) * create a child node below given parent node * loc is the character of the node (consult source code of mkstr for more information) * returns: pointer to said node or NULL if function fails int mkstr(struct nod *nod, char *str) * fit string into tree if it does not already exist * warning: string has to be null-byte terminated * returns: the assigned ID of the string, 0 if string is already inside tree, or -1 if function fails int gentree(struct nod *nod, char *strs, char *delim) * generate tree from character seperated strings * if delim is NULL, then "\n" is assumed * warning: seperation character is '\n' * returns: 0 if ok or -1 if function fails int streecmp(struct nod *nod, char *str) * traverse tree and search for str * returns: id of string or 0 if there is no match test.c provides a practical example for comparing against HTTP header fields LEAKS LEAKS file contains the most recent valgrind memory leaks dump ran on test.c. TODO * feat: ++strong++ and --loose-- comparison COMMITS Each commit is prefixed with an indicator token of what the change is *mostly* about. List of tokens is: * repo: change docs or code style * feat: implement new change * fix: implement fix for a bug