/* * "$Id: filter.c,v 1.1.1.3.2.1 2002/12/13 22:54:13 jlovell Exp $" * * File type conversion routines for the Common UNIX Printing System (CUPS). * * Copyright 1997-2002 by Easy Software Products, all rights reserved. * * These coded instructions, statements, and computer programs are the * property of Easy Software Products and are protected by Federal * copyright law. Distribution and use rights are outlined in the file * "LICENSE.txt" which should have been included with this file. If this * file is missing or damaged please contact Easy Software Products * at: * * Attn: CUPS Licensing Information * Easy Software Products * 44141 Airport View Drive, Suite 204 * Hollywood, Maryland 20636-3111 USA * * Voice: (301) 373-9603 * EMail: cups-info@cups.org * WWW: http://www.cups.org * * Contents: * * mimeAddFilter() - Add a filter to the current MIME database. * mimeFilter() - Find the fastest way to convert from one type to another. * compare() - Compare two filter types... * lookup() - Lookup a filter... */ /* * Include necessary headers... */ #include #include #include #include #include "mime.h" /* * Local functions... */ static int compare(mime_filter_t *, mime_filter_t *); static mime_filter_t *lookup(mime_t *, mime_type_t *, mime_type_t *); /* * 'mimeAddFilter()' - Add a filter to the current MIME database. */ mime_filter_t * /* O - New filter */ mimeAddFilter(mime_t *mime, /* I - MIME database */ mime_type_t *src, /* I - Source type */ mime_type_t *dst, /* I - Destination type */ int cost, /* I - Relative time/resource cost */ const char *filter) /* I - Filter program to run */ { mime_filter_t *temp; /* New filter */ /* * Range-check the input... */ if (mime == NULL || src == NULL || dst == NULL || filter == NULL) return (NULL); if (strlen(filter) > (MIME_MAX_FILTER - 1)) return (NULL); /* * See if we already have an existing filter for the given source and * destination... */ if ((temp = lookup(mime, src, dst)) != NULL) { /* * Yup, does the existing filter have a higher cost? If so, copy the * filter and cost to the existing filter entry and return it... */ if (temp->cost > cost) { temp->cost = cost; strlcpy(temp->filter, filter, sizeof(temp->filter)); } } else { /* * Nope, add a new one... */ if (mime->num_filters == 0) temp = malloc(sizeof(mime_filter_t)); else temp = realloc(mime->filters, sizeof(mime_filter_t) * (mime->num_filters + 1)); if (temp == NULL) return (NULL); mime->filters = temp; temp += mime->num_filters; mime->num_filters ++; /* * Copy the information over and sort if necessary... */ temp->src = src; temp->dst = dst; temp->cost = cost; strlcpy(temp->filter, filter, sizeof(temp->filter)); if (mime->num_filters > 1) qsort(mime->filters, mime->num_filters, sizeof(mime_filter_t), (int (*)(const void *, const void *))compare); } /* * Return the new/updated filter... */ return (temp); } /* * 'mimeFilter()' - Find the fastest way to convert from one type to another. */ mime_filter_t * /* O - Array of filters to run */ mimeFilter(mime_t *mime, /* I - MIME database */ mime_type_t *src, /* I - Source file type */ mime_type_t *dst, /* I - Destination file type */ int *num_filters) /* O - Number of filters to run */ { int i, j, /* Looping vars */ num_temp, /* Number of temporary filters */ num_mintemp, /* Number of filters in the minimum */ cost, /* Current cost */ mincost; /* Current minimum */ mime_filter_t *temp, /* Temporary filter */ *mintemp, /* Current minimum */ *mincurrent, /* Current filter for minimum */ *current, /* Current filter */ *filters; /* Filters to use */ /* * Range-check the input... */ if (mime == NULL || src == NULL || dst == NULL || num_filters == NULL) return (NULL); *num_filters = 0; /* * See if there is a filter that can convert the files directly... */ if ((temp = lookup(mime, src, dst)) != NULL) { /* * Got a direct filter! */ if ((filters = (mime_filter_t *)malloc(sizeof(mime_filter_t))) == NULL) return (NULL); memcpy(filters, temp, sizeof(mime_filter_t)); *num_filters = 1; return (filters); } /* * OK, now look for filters from the source type to any other type... */ mincost = 9999999; mintemp = NULL; num_mintemp = 0; mincurrent = NULL; for (i = mime->num_filters, current = mime->filters; i > 0; i --, current ++) if (current->src == src) { /* * See if we have any filters that can convert from the destination type * of this filter to the final type... */ if ((temp = mimeFilter(mime, current->dst, dst, &num_temp)) == NULL) continue; /* * Found a match; see if this one is less costly than the last (if * any...) */ for (j = 0, cost = 0; j < num_temp; j ++) cost += temp[j].cost; if (cost < mincost) { if (mintemp != NULL) free(mintemp); mincost = cost; mintemp = temp; num_mintemp = num_temp; mincurrent = current; } else free(temp); } if (mintemp != NULL) { /* * Hey, we got a match! Add the current filter to the beginning of the * filter list... */ filters = (mime_filter_t *)realloc(mintemp, sizeof(mime_filter_t) * (num_mintemp + 1)); if (filters == NULL) { *num_filters = 0; return (NULL); } memmove(filters + 1, filters, num_mintemp * sizeof(mime_filter_t)); memcpy(filters, mincurrent, sizeof(mime_filter_t)); *num_filters = num_mintemp + 1; return (filters); } return (NULL); } /* * 'compare()' - Compare two filter types... */ static int /* O - Comparison result */ compare(mime_filter_t *f0, /* I - First filter */ mime_filter_t *f1) /* I - Second filter */ { int i; /* Result of comparison */ if ((i = strcmp(f0->src->super, f1->src->super)) == 0) if ((i = strcmp(f0->src->type, f1->src->type)) == 0) if ((i = strcmp(f0->dst->super, f1->dst->super)) == 0) i = strcmp(f0->dst->type, f1->dst->type); return (i); } /* * 'lookup()' - Lookup a filter... */ static mime_filter_t * /* O - Filter for src->dst */ lookup(mime_t *mime, /* I - MIME database */ mime_type_t *src, /* I - Source type */ mime_type_t *dst) /* I - Destination type */ { mime_filter_t key; /* Key record for filter search */ if (mime->num_filters == 0) return (NULL); key.src = src; key.dst = dst; return ((mime_filter_t *)bsearch(&key, mime->filters, mime->num_filters, sizeof(mime_filter_t), (int (*)(const void *, const void *))compare)); } /* * End of "$Id: filter.c,v 1.1.1.3.2.1 2002/12/13 22:54:13 jlovell Exp $". */