diff options
author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-05-01 16:24:15 +0200 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-05-01 16:24:15 +0200 |
commit | a30ba67504ffd12c4db499adbb5ce47a7d1f6036 (patch) | |
tree | 9ae1a7e3849dda6bbb5c578232f6f2fa5b2e7e7e /xml/mxml-index.c | |
parent | 89e99e8a827859729729dfc92d74be4a8f96f1a4 (diff) | |
parent | 094535c010320967639e8e86f974d878e80baa72 (diff) |
New release 1.7.0
Diffstat (limited to 'xml/mxml-index.c')
-rw-r--r-- | xml/mxml-index.c | 662 |
1 files changed, 662 insertions, 0 deletions
diff --git a/xml/mxml-index.c b/xml/mxml-index.c new file mode 100644 index 0000000..b6efc66 --- /dev/null +++ b/xml/mxml-index.c @@ -0,0 +1,662 @@ +/* + * "$Id: mxml-index.c 426 2011-01-01 23:42:17Z mike $" + * + * Index support code for Mini-XML, a small XML-like file parsing library. + * + * Copyright 2003-2011 by Michael R Sweet. + * + * These coded instructions, statements, and computer programs are the + * property of Michael R Sweet and are protected by Federal copyright + * law. Distribution and use rights are outlined in the file "COPYING" + * which should have been included with this file. If this file is + * missing or damaged, see the license at: + * + * http://www.minixml.org/ + * + * Contents: + * + */ + +/* + * Include necessary headers... + */ + +#include "config.h" +#include "mxml.h" + + +/* + * Sort functions... + */ + +static int index_compare(mxml_index_t *ind, mxml_node_t *first, + mxml_node_t *second); +static int index_find(mxml_index_t *ind, const char *element, + const char *value, mxml_node_t *node); +static void index_sort(mxml_index_t *ind, int left, int right); + + +/* + * 'mxmlIndexDelete()' - Delete an index. + */ + +void +mxmlIndexDelete(mxml_index_t *ind) /* I - Index to delete */ +{ + /* + * Range check input.. + */ + + if (!ind) + return; + + /* + * Free memory... + */ + + if (ind->attr) + free(ind->attr); + + if (ind->alloc_nodes) + free(ind->nodes); + + free(ind); +} + + +/* + * 'mxmlIndexEnum()' - Return the next node in the index. + * + * Nodes are returned in the sorted order of the index. + */ + +mxml_node_t * /* O - Next node or NULL if there is none */ +mxmlIndexEnum(mxml_index_t *ind) /* I - Index to enumerate */ +{ + /* + * Range check input... + */ + + if (!ind) + return (NULL); + + /* + * Return the next node... + */ + + if (ind->cur_node < ind->num_nodes) + return (ind->nodes[ind->cur_node ++]); + else + return (NULL); +} + + +/* + * 'mxmlIndexFind()' - Find the next matching node. + * + * You should call mxmlIndexReset() prior to using this function for + * the first time with a particular set of "element" and "value" + * strings. Passing NULL for both "element" and "value" is equivalent + * to calling mxmlIndexEnum(). + */ + +mxml_node_t * /* O - Node or NULL if none found */ +mxmlIndexFind(mxml_index_t *ind, /* I - Index to search */ + const char *element, /* I - Element name to find, if any */ + const char *value) /* I - Attribute value, if any */ +{ + int diff, /* Difference between names */ + current, /* Current entity in search */ + first, /* First entity in search */ + last; /* Last entity in search */ + + +#ifdef DEBUG + printf("mxmlIndexFind(ind=%p, element=\"%s\", value=\"%s\")\n", + ind, element ? element : "(null)", value ? value : "(null)"); +#endif /* DEBUG */ + + /* + * Range check input... + */ + + if (!ind || (!ind->attr && value)) + { +#ifdef DEBUG + puts(" returning NULL..."); + printf(" ind->attr=\"%s\"\n", ind->attr ? ind->attr : "(null)"); +#endif /* DEBUG */ + + return (NULL); + } + + /* + * If both element and value are NULL, just enumerate the nodes in the + * index... + */ + + if (!element && !value) + return (mxmlIndexEnum(ind)); + + /* + * If there are no nodes in the index, return NULL... + */ + + if (!ind->num_nodes) + { +#ifdef DEBUG + puts(" returning NULL..."); + puts(" no nodes!"); +#endif /* DEBUG */ + + return (NULL); + } + + /* + * If cur_node == 0, then find the first matching node... + */ + + if (ind->cur_node == 0) + { + /* + * Find the first node using a modified binary search algorithm... + */ + + first = 0; + last = ind->num_nodes - 1; + +#ifdef DEBUG + printf(" find first time, num_nodes=%d...\n", ind->num_nodes); +#endif /* DEBUG */ + + while ((last - first) > 1) + { + current = (first + last) / 2; + +#ifdef DEBUG + printf(" first=%d, last=%d, current=%d\n", first, last, current); +#endif /* DEBUG */ + + if ((diff = index_find(ind, element, value, ind->nodes[current])) == 0) + { + /* + * Found a match, move back to find the first... + */ + +#ifdef DEBUG + puts(" match!"); +#endif /* DEBUG */ + + while (current > 0 && + !index_find(ind, element, value, ind->nodes[current - 1])) + current --; + +#ifdef DEBUG + printf(" returning first match=%d\n", current); +#endif /* DEBUG */ + + /* + * Return the first match and save the index to the next... + */ + + ind->cur_node = current + 1; + + return (ind->nodes[current]); + } + else if (diff < 0) + last = current; + else + first = current; + +#ifdef DEBUG + printf(" diff=%d\n", diff); +#endif /* DEBUG */ + } + + /* + * If we get this far, then we found exactly 0 or 1 matches... + */ + + for (current = first; current <= last; current ++) + if (!index_find(ind, element, value, ind->nodes[current])) + { + /* + * Found exactly one (or possibly two) match... + */ + +#ifdef DEBUG + printf(" returning only match %d...\n", current); +#endif /* DEBUG */ + + ind->cur_node = current + 1; + + return (ind->nodes[current]); + } + + /* + * No matches... + */ + + ind->cur_node = ind->num_nodes; + +#ifdef DEBUG + puts(" returning NULL..."); +#endif /* DEBUG */ + + return (NULL); + } + else if (ind->cur_node < ind->num_nodes && + !index_find(ind, element, value, ind->nodes[ind->cur_node])) + { + /* + * Return the next matching node... + */ + +#ifdef DEBUG + printf(" returning next match %d...\n", ind->cur_node); +#endif /* DEBUG */ + + return (ind->nodes[ind->cur_node ++]); + } + + /* + * If we get this far, then we have no matches... + */ + + ind->cur_node = ind->num_nodes; + +#ifdef DEBUG + puts(" returning NULL..."); +#endif /* DEBUG */ + + return (NULL); +} + + +/* + * 'mxmlIndexGetCount()' - Get the number of nodes in an index. + * + * @since Mini-XML 2.7@ + */ + +int /* I - Number of nodes in index */ +mxmlIndexGetCount(mxml_index_t *ind) /* I - Index of nodes */ +{ + /* + * Range check input... + */ + + if (!ind) + return (0); + + /* + * Return the number of nodes in the index... + */ + + return (ind->num_nodes); +} + + +/* + * 'mxmlIndexNew()' - Create a new index. + * + * The index will contain all nodes that contain the named element and/or + * attribute. If both "element" and "attr" are NULL, then the index will + * contain a sorted list of the elements in the node tree. Nodes are + * sorted by element name and optionally by attribute value if the "attr" + * argument is not NULL. + */ + +mxml_index_t * /* O - New index */ +mxmlIndexNew(mxml_node_t *node, /* I - XML node tree */ + const char *element, /* I - Element to index or NULL for all */ + const char *attr) /* I - Attribute to index or NULL for none */ +{ + mxml_index_t *ind; /* New index */ + mxml_node_t *current, /* Current node in index */ + **temp; /* Temporary node pointer array */ + + + /* + * Range check input... + */ + +#ifdef DEBUG + printf("mxmlIndexNew(node=%p, element=\"%s\", attr=\"%s\")\n", + node, element ? element : "(null)", attr ? attr : "(null)"); +#endif /* DEBUG */ + + if (!node) + return (NULL); + + /* + * Create a new index... + */ + + if ((ind = calloc(1, sizeof(mxml_index_t))) == NULL) + { + mxml_error("Unable to allocate %d bytes for index - %s", + sizeof(mxml_index_t), strerror(errno)); + return (NULL); + } + + if (attr) + ind->attr = strdup(attr); + + if (!element && !attr) + current = node; + else + current = mxmlFindElement(node, node, element, attr, NULL, MXML_DESCEND); + + while (current) + { + if (ind->num_nodes >= ind->alloc_nodes) + { + if (!ind->alloc_nodes) + temp = malloc(64 * sizeof(mxml_node_t *)); + else + temp = realloc(ind->nodes, (ind->alloc_nodes + 64) * sizeof(mxml_node_t *)); + + if (!temp) + { + /* + * Unable to allocate memory for the index, so abort... + */ + + mxml_error("Unable to allocate %d bytes for index: %s", + (ind->alloc_nodes + 64) * sizeof(mxml_node_t *), + strerror(errno)); + + mxmlIndexDelete(ind); + return (NULL); + } + + ind->nodes = temp; + ind->alloc_nodes += 64; + } + + ind->nodes[ind->num_nodes ++] = current; + + current = mxmlFindElement(current, node, element, attr, NULL, MXML_DESCEND); + } + + /* + * Sort nodes based upon the search criteria... + */ + +#ifdef DEBUG + { + int i; /* Looping var */ + + + printf("%d node(s) in index.\n\n", ind->num_nodes); + + if (attr) + { + printf("Node Address Element %s\n", attr); + puts("-------- -------- -------------- ------------------------------"); + + for (i = 0; i < ind->num_nodes; i ++) + printf("%8d %-8p %-14.14s %s\n", i, ind->nodes[i], + ind->nodes[i]->value.element.name, + mxmlElementGetAttr(ind->nodes[i], attr)); + } + else + { + puts("Node Address Element"); + puts("-------- -------- --------------"); + + for (i = 0; i < ind->num_nodes; i ++) + printf("%8d %-8p %s\n", i, ind->nodes[i], + ind->nodes[i]->value.element.name); + } + + putchar('\n'); + } +#endif /* DEBUG */ + + if (ind->num_nodes > 1) + index_sort(ind, 0, ind->num_nodes - 1); + +#ifdef DEBUG + { + int i; /* Looping var */ + + + puts("After sorting:\n"); + + if (attr) + { + printf("Node Address Element %s\n", attr); + puts("-------- -------- -------------- ------------------------------"); + + for (i = 0; i < ind->num_nodes; i ++) + printf("%8d %-8p %-14.14s %s\n", i, ind->nodes[i], + ind->nodes[i]->value.element.name, + mxmlElementGetAttr(ind->nodes[i], attr)); + } + else + { + puts("Node Address Element"); + puts("-------- -------- --------------"); + + for (i = 0; i < ind->num_nodes; i ++) + printf("%8d %-8p %s\n", i, ind->nodes[i], + ind->nodes[i]->value.element.name); + } + + putchar('\n'); + } +#endif /* DEBUG */ + + /* + * Return the new index... + */ + + return (ind); +} + + +/* + * 'mxmlIndexReset()' - Reset the enumeration/find pointer in the index and + * return the first node in the index. + * + * This function should be called prior to using mxmlIndexEnum() or + * mxmlIndexFind() for the first time. + */ + +mxml_node_t * /* O - First node or NULL if there is none */ +mxmlIndexReset(mxml_index_t *ind) /* I - Index to reset */ +{ +#ifdef DEBUG + printf("mxmlIndexReset(ind=%p)\n", ind); +#endif /* DEBUG */ + + /* + * Range check input... + */ + + if (!ind) + return (NULL); + + /* + * Set the index to the first element... + */ + + ind->cur_node = 0; + + /* + * Return the first node... + */ + + if (ind->num_nodes) + return (ind->nodes[0]); + else + return (NULL); +} + + +/* + * 'index_compare()' - Compare two nodes. + */ + +static int /* O - Result of comparison */ +index_compare(mxml_index_t *ind, /* I - Index */ + mxml_node_t *first, /* I - First node */ + mxml_node_t *second) /* I - Second node */ +{ + int diff; /* Difference */ + + + /* + * Check the element name... + */ + + if ((diff = strcmp(first->value.element.name, + second->value.element.name)) != 0) + return (diff); + + /* + * Check the attribute value... + */ + + if (ind->attr) + { + if ((diff = strcmp(mxmlElementGetAttr(first, ind->attr), + mxmlElementGetAttr(second, ind->attr))) != 0) + return (diff); + } + + /* + * No difference, return 0... + */ + + return (0); +} + + +/* + * 'index_find()' - Compare a node with index values. + */ + +static int /* O - Result of comparison */ +index_find(mxml_index_t *ind, /* I - Index */ + const char *element, /* I - Element name or NULL */ + const char *value, /* I - Attribute value or NULL */ + mxml_node_t *node) /* I - Node */ +{ + int diff; /* Difference */ + + + /* + * Check the element name... + */ + + if (element) + { + if ((diff = strcmp(element, node->value.element.name)) != 0) + return (diff); + } + + /* + * Check the attribute value... + */ + + if (value) + { + if ((diff = strcmp(value, mxmlElementGetAttr(node, ind->attr))) != 0) + return (diff); + } + + /* + * No difference, return 0... + */ + + return (0); +} + + +/* + * 'index_sort()' - Sort the nodes in the index... + * + * This function implements the classic quicksort algorithm... + */ + +static void +index_sort(mxml_index_t *ind, /* I - Index to sort */ + int left, /* I - Left node in partition */ + int right) /* I - Right node in partition */ +{ + mxml_node_t *pivot, /* Pivot node */ + *temp; /* Swap node */ + int templ, /* Temporary left node */ + tempr; /* Temporary right node */ + + + /* + * Loop until we have sorted all the way to the right... + */ + + do + { + /* + * Sort the pivot in the current partition... + */ + + pivot = ind->nodes[left]; + + for (templ = left, tempr = right; templ < tempr;) + { + /* + * Move left while left node <= pivot node... + */ + + while ((templ < right) && + index_compare(ind, ind->nodes[templ], pivot) <= 0) + templ ++; + + /* + * Move right while right node > pivot node... + */ + + while ((tempr > left) && + index_compare(ind, ind->nodes[tempr], pivot) > 0) + tempr --; + + /* + * Swap nodes if needed... + */ + + if (templ < tempr) + { + temp = ind->nodes[templ]; + ind->nodes[templ] = ind->nodes[tempr]; + ind->nodes[tempr] = temp; + } + } + + /* + * When we get here, the right (tempr) node is the new position for the + * pivot node... + */ + + if (index_compare(ind, pivot, ind->nodes[tempr]) > 0) + { + ind->nodes[left] = ind->nodes[tempr]; + ind->nodes[tempr] = pivot; + } + + /* + * Recursively sort the left partition as needed... + */ + + if (left < (tempr - 1)) + index_sort(ind, left, tempr - 1); + } + while (right > (left = tempr + 1)); +} + + +/* + * End of "$Id: mxml-index.c 426 2011-01-01 23:42:17Z mike $". + */ |