/* * "$Id: ppdx.c 3835 2012-05-23 22:57:19Z msweet $" * * Example code for encoding and decoding large amounts of data in a PPD file. * This would typically be used in a driver to save configuration/state * information that could be used by an application. * * Copyright 2012 by Apple Inc. * * These coded instructions, statements, and computer programs are the * property of Apple Inc. 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 * file is missing or damaged, see the license at "http://www.cups.org/". * * This file is subject to the Apple OS-Developed Software exception. * * Contents: * * ppdxReadData() - Read encoded data from a ppd_file_t *. * ppdxWriteData() - Writes encoded data to stderr using PPD: messages. */ /* * Include necessary headers... */ #include "ppdx.h" #include <stdio.h> #include <stdlib.h> #include <string.h> #include <zlib.h> /* For compression of the data */ /* * Constants... */ #define PPDX_MAX_VALUE (PPD_MAX_LINE - PPD_MAX_NAME - 4) /* Max value length with delimiters + nul */ #define PPDX_MAX_CHUNK (PPDX_MAX_VALUE * 3 / 4) /* Max length of each chunk when Base64-encoded */ /* * 'ppdxReadData()' - Read encoded data from a ppd_file_t *. * * Reads chunked data in the PPD file "ppd" using the prefix "name". Returns * an allocated pointer to the data (which is nul-terminated for convenience) * along with the length of the data in the variable pointed to by "datasize", * which can be NULL to indicate the caller doesn't need the length. * * Returns NULL if no data is present in the PPD with the prefix. */ void * /* O - Data or NULL */ ppdxReadData(ppd_file_t *ppd, /* I - PPD file */ const char *name, /* I - Keyword prefix */ size_t *datasize) /* O - Size of data or NULL for don't care */ { char keyword[PPD_MAX_NAME], /* Keyword name */ decoded[PPDX_MAX_CHUNK + 1]; /* Decoded string */ unsigned chunk = 0; /* Current chunk number */ int len; /* Length of current chunk */ ppd_attr_t *attr; /* Keyword/value from PPD file */ Bytef *data; /* Pointer to data */ size_t alloc_size; /* Allocated size of data buffer */ z_stream decomp; /* Decompressor stream */ int error; /* Error/status from inflate() */ /* * Range check input... */ if (datasize) *datasize = 0; if (!ppd || !name) return (NULL); /* * First see if there are any instances of the named keyword in the PPD... */ snprintf(keyword, sizeof(keyword), "%s%04x", name, chunk); if ((attr = ppdFindAttr(ppd, keyword, NULL)) == NULL) return (NULL); /* * Allocate some memory and start decoding... */ data = malloc(257); alloc_size = 256; memset(&decomp, 0, sizeof(decomp)); decomp.next_out = data; decomp.avail_out = 256; inflateInit(&decomp); do { /* * Grab the data from the current attribute and decode it... */ len = sizeof(decoded); if (!httpDecode64_2(decoded, &len, attr->value) || len == 0) break; // printf("chunk %04x has length %d\n", chunk, len); /* * Decompress this chunk... */ decomp.next_in = decoded; decomp.avail_in = len; do { Bytef *temp; /* Temporary pointer */ size_t temp_size; /* Temporary allocation size */ // printf("Before inflate: avail_in=%d, avail_out=%d\n", decomp.avail_in, // decomp.avail_out); if ((error = inflate(&decomp, Z_NO_FLUSH)) < Z_OK) { fprintf(stderr, "ERROR: inflate returned %d (%s)\n", error, decomp.msg); break; } // printf("After inflate: avail_in=%d, avail_out=%d, error=%d\n", // decomp.avail_in, decomp.avail_out, error); if (decomp.avail_out == 0) { if (alloc_size < 2048) temp_size = alloc_size * 2; else if (alloc_size < PPDX_MAX_DATA) temp_size = alloc_size + 2048; else break; if ((temp = realloc(data, temp_size + 1)) == NULL) { free(data); return (NULL); } decomp.next_out = temp + (decomp.next_out - data); decomp.avail_out = temp_size - alloc_size; data = temp; alloc_size = temp_size; } } while (decomp.avail_in > 0); chunk ++; snprintf(keyword, sizeof(keyword), "%s%04x", name, chunk); } while ((attr = ppdFindAttr(ppd, keyword, NULL)) != NULL); inflateEnd(&decomp); /* * Nul-terminate the data (usually a string)... */ *(decomp.next_out) = '\0'; if (datasize) *datasize = decomp.next_out - data; return (data); } /* * 'ppdxWriteData()' - Writes encoded data to stderr using PPD: messages. * * Writes chunked data to the PPD file using PPD: messages sent to stderr for * cupsd. "name" must be a valid PPD keyword string whose length is less than * 37 characters to allow for chunk numbering. "data" provides a pointer to the * data to be written, and "datasize" provides the length. */ extern void ppdxWriteData(const char *name, /* I - Base name of keyword */ const void *data, /* I - Data to write */ size_t datasize) /* I - Number of bytes in data */ { char buffer[PPDX_MAX_CHUNK], /* Chunk buffer */ encoded[PPDX_MAX_VALUE + 1], /* Encoded data */ pair[PPD_MAX_LINE], /* name=value pair */ line[PPDX_MAX_STATUS], /* Line buffer */ *lineptr, /* Current position in line buffer */ *lineend; /* End of line buffer */ unsigned chunk = 0; /* Current chunk number */ int len; /* Length of current chunk */ z_stream comp; /* Compressor stream */ int error; /* Error/status from deflate() */ /* * Range check input... */ if (!name || (!data && datasize > 0) || datasize > PPDX_MAX_DATA) return; strlcpy(line, "PPD:", sizeof(line)); lineptr = line + 4; lineend = line + sizeof(line) - 2; if (datasize > 0) { /* * Compress and encode output... */ memset(&comp, 0, sizeof(comp)); comp.next_in = (Bytef *)data; comp.avail_in = datasize; deflateInit(&comp, 9); do { /* * Compress a chunk... */ comp.next_out = buffer; comp.avail_out = sizeof(buffer); if ((error = deflate(&comp, Z_FINISH)) < Z_OK) { fprintf(stderr, "ERROR: deflate returned %d (%s)\n", error, comp.msg); break; } /* * Write a chunk... */ len = sizeof(buffer) - comp.avail_out; httpEncode64_2(encoded, sizeof(encoded), buffer, len); len = (int)snprintf(pair, sizeof(pair), " %s%04x=%s", name, chunk, encoded); #ifdef DEBUG fprintf(stderr, "DEBUG: *%s%04x: \"%s\"\n", name, chunk, encoded); #endif /* DEBUG */ if ((lineptr + len) >= lineend) { *lineptr++ = '\n'; *lineptr = '\0'; fputs(line, stderr); lineptr = line + 4; } strlcpy(lineptr, pair, lineend - lineptr); lineptr += len; /* * Setup for the next one... */ chunk ++; } while (comp.avail_out == 0); } deflateEnd(&comp); /* * Write a trailing empty chunk to signal EOD... */ len = (int)snprintf(pair, sizeof(pair), " %s%04x=\"\"", name, chunk); #ifdef DEBUG fprintf(stderr, "DEBUG: *%s%04x: \"\"\n", name, chunk); #endif /* DEBUG */ if ((lineptr + len) >= lineend) { *lineptr++ = '\n'; *lineptr = '\0'; fputs(line, stderr); lineptr = line + 4; } strlcpy(lineptr, pair, lineend - lineptr); lineptr += len; *lineptr++ = '\n'; *lineptr = '\0'; fputs(line, stderr); } /* * End of "$Id: ppdx.c 3835 2012-05-23 22:57:19Z msweet $". */