diff options
Diffstat (limited to 'jffsX-utils/compr.c')
| -rw-r--r-- | jffsX-utils/compr.c | 538 |
1 files changed, 538 insertions, 0 deletions
diff --git a/jffsX-utils/compr.c b/jffsX-utils/compr.c new file mode 100644 index 0000000..cb4432e --- /dev/null +++ b/jffsX-utils/compr.c @@ -0,0 +1,538 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>, + * University of Szeged, Hungary + * + * For licensing information, see the file 'LICENCE' in this directory + * in the jffs2 directory. + */ + +#include "compr.h" +#include <string.h> +#include <stdlib.h> +#include <linux/jffs2.h> + +#define FAVOUR_LZO_PERCENT 80 + +extern int page_size; + +/* LIST IMPLEMENTATION (from linux/list.h) */ + +#define LIST_HEAD_INIT(name) { &(name), &(name) } + +#define LIST_HEAD(name) \ + struct list_head name = LIST_HEAD_INIT(name) + +static inline void __list_add(struct list_head *new, + struct list_head *prev, + struct list_head *next) +{ + next->prev = new; + new->next = next; + new->prev = prev; + prev->next = new; +} + +static inline void list_add(struct list_head *new, struct list_head *head) +{ + __list_add(new, head, head->next); +} + +static inline void list_add_tail(struct list_head *new, struct list_head *head) +{ + __list_add(new, head->prev, head); +} + +static inline void __list_del(struct list_head *prev, struct list_head *next) +{ + next->prev = prev; + prev->next = next; +} + +static inline void list_del(struct list_head *entry) +{ + __list_del(entry->prev, entry->next); + entry->next = (void *) 0; + entry->prev = (void *) 0; +} + +#define list_entry(ptr, type, member) \ + ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member))) + +#define list_for_each_entry(pos, head, member) \ + for (pos = list_entry((head)->next, typeof(*pos), member); \ + &pos->member != (head); \ + pos = list_entry(pos->member.next, typeof(*pos), member)) + + +/* Available compressors are on this list */ +static LIST_HEAD(jffs2_compressor_list); + +/* Actual compression mode */ +static int jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; + +void jffs2_set_compression_mode(int mode) +{ + jffs2_compression_mode = mode; +} + +int jffs2_get_compression_mode(void) +{ + return jffs2_compression_mode; +} + +/* Statistics for blocks stored without compression */ +static uint32_t none_stat_compr_blocks=0,none_stat_decompr_blocks=0,none_stat_compr_size=0; + +/* Compression test stuffs */ + +static int jffs2_compression_check = 0; + +static unsigned char *jffs2_compression_check_buf = NULL; + +void jffs2_compression_check_set(int yesno) +{ + jffs2_compression_check = yesno; +} + +int jffs2_compression_check_get(void) +{ + return jffs2_compression_check; +} + +static int jffs2_error_cnt = 0; + +int jffs2_compression_check_errorcnt_get(void) +{ + return jffs2_error_cnt; +} + +#define JFFS2_BUFFER_FILL 0x55 + +/* Called before compression (if compression_check is setted) to prepare + the buffer for buffer overflow test */ +static void jffs2_decompression_test_prepare(unsigned char *buf, int size) +{ + memset(buf,JFFS2_BUFFER_FILL,size+1); +} + +/* Called after compression (if compression_check is setted) to test the result */ +static void jffs2_decompression_test(struct jffs2_compressor *compr, + unsigned char *data_in, unsigned char *output_buf, + uint32_t cdatalen, uint32_t datalen, uint32_t buf_size) +{ + uint32_t i; + + /* buffer overflow test */ + for (i=buf_size;i>cdatalen;i--) { + if (output_buf[i]!=JFFS2_BUFFER_FILL) { + fprintf(stderr,"COMPR_ERROR: buffer overflow at %s. " + "(bs=%d csize=%d b[%d]=%d)\n", compr->name, + buf_size, cdatalen, i, (int)(output_buf[i])); + jffs2_error_cnt++; + return; + } + } + /* allocing temporary buffer for decompression */ + if (!jffs2_compression_check_buf) { + jffs2_compression_check_buf = malloc(page_size); + if (!jffs2_compression_check_buf) { + fprintf(stderr,"No memory for buffer allocation. Compression check disabled.\n"); + jffs2_compression_check = 0; + return; + } + } + /* decompressing */ + if (!compr->decompress) { + fprintf(stderr,"JFFS2 compression check: there is no decompress function at %s.\n", compr->name); + jffs2_error_cnt++; + return; + } + if (compr->decompress(output_buf,jffs2_compression_check_buf,cdatalen,datalen)) { + fprintf(stderr,"JFFS2 compression check: decompression failed at %s.\n", compr->name); + jffs2_error_cnt++; + } + /* validate decompression */ + else { + for (i=0;i<datalen;i++) { + if (data_in[i]!=jffs2_compression_check_buf[i]) { + fprintf(stderr,"JFFS2 compression check: data mismatch at %s (pos %d).\n", compr->name, i); + jffs2_error_cnt++; + break; + } + } + } +} + +/* + * Return 1 to use this compression + */ +static int jffs2_is_best_compression(struct jffs2_compressor *this, + struct jffs2_compressor *best, uint32_t size, uint32_t bestsize) +{ + switch (jffs2_compression_mode) { + case JFFS2_COMPR_MODE_SIZE: + if (bestsize > size) + return 1; + return 0; + case JFFS2_COMPR_MODE_FAVOURLZO: + if ((this->compr == JFFS2_COMPR_LZO) && (bestsize > size)) + return 1; + if ((best->compr != JFFS2_COMPR_LZO) && (bestsize > size)) + return 1; + if ((this->compr == JFFS2_COMPR_LZO) && (bestsize > (size * FAVOUR_LZO_PERCENT / 100))) + return 1; + if ((bestsize * FAVOUR_LZO_PERCENT / 100) > size) + return 1; + + return 0; + } + /* Shouldn't happen */ + return 0; +} + +/* jffs2_compress: + * @data: Pointer to uncompressed data + * @cdata: Pointer to returned pointer to buffer for compressed data + * @datalen: On entry, holds the amount of data available for compression. + * On exit, expected to hold the amount of data actually compressed. + * @cdatalen: On entry, holds the amount of space available for compressed + * data. On exit, expected to hold the actual size of the compressed + * data. + * + * Returns: Lower byte to be stored with data indicating compression type used. + * Zero is used to show that the data could not be compressed - the + * compressed version was actually larger than the original. + * Upper byte will be used later. (soon) + * + * If the cdata buffer isn't large enough to hold all the uncompressed data, + * jffs2_compress should compress as much as will fit, and should set + * *datalen accordingly to show the amount of data which were compressed. + */ +uint16_t jffs2_compress( unsigned char *data_in, unsigned char **cpage_out, + uint32_t *datalen, uint32_t *cdatalen) +{ + int ret = JFFS2_COMPR_NONE; + int compr_ret; + struct jffs2_compressor *this, *best=NULL; + unsigned char *output_buf = NULL, *tmp_buf; + uint32_t orig_slen, orig_dlen; + uint32_t best_slen=0, best_dlen=0; + + switch (jffs2_compression_mode) { + case JFFS2_COMPR_MODE_NONE: + break; + case JFFS2_COMPR_MODE_PRIORITY: + orig_slen = *datalen; + orig_dlen = *cdatalen; + output_buf = malloc(orig_dlen+jffs2_compression_check); + if (!output_buf) { + fprintf(stderr,"mkfs.jffs2: No memory for compressor allocation. Compression failed.\n"); + goto out; + } + list_for_each_entry(this, &jffs2_compressor_list, list) { + /* Skip decompress-only backwards-compatibility and disabled modules */ + if ((!this->compress)||(this->disabled)) + continue; + + this->usecount++; + + if (jffs2_compression_check) /*preparing output buffer for testing buffer overflow */ + jffs2_decompression_test_prepare(output_buf, orig_dlen); + + *datalen = orig_slen; + *cdatalen = orig_dlen; + compr_ret = this->compress(data_in, output_buf, datalen, cdatalen); + this->usecount--; + if (!compr_ret) { + ret = this->compr; + this->stat_compr_blocks++; + this->stat_compr_orig_size += *datalen; + this->stat_compr_new_size += *cdatalen; + if (jffs2_compression_check) + jffs2_decompression_test(this, data_in, output_buf, *cdatalen, *datalen, orig_dlen); + break; + } + } + if (ret == JFFS2_COMPR_NONE) free(output_buf); + break; + case JFFS2_COMPR_MODE_FAVOURLZO: + case JFFS2_COMPR_MODE_SIZE: + orig_slen = *datalen; + orig_dlen = *cdatalen; + list_for_each_entry(this, &jffs2_compressor_list, list) { + uint32_t needed_buf_size; + + if (jffs2_compression_mode == JFFS2_COMPR_MODE_FAVOURLZO) + needed_buf_size = orig_slen + jffs2_compression_check; + else + needed_buf_size = orig_dlen + jffs2_compression_check; + + /* Skip decompress-only backwards-compatibility and disabled modules */ + if ((!this->compress)||(this->disabled)) + continue; + /* Allocating memory for output buffer if necessary */ + if ((this->compr_buf_size < needed_buf_size) && (this->compr_buf)) { + free(this->compr_buf); + this->compr_buf_size=0; + this->compr_buf=NULL; + } + if (!this->compr_buf) { + tmp_buf = malloc(needed_buf_size); + if (!tmp_buf) { + fprintf(stderr,"mkfs.jffs2: No memory for compressor allocation. (%d bytes)\n",orig_dlen); + continue; + } + else { + this->compr_buf = tmp_buf; + this->compr_buf_size = orig_dlen; + } + } + this->usecount++; + if (jffs2_compression_check) /*preparing output buffer for testing buffer overflow */ + jffs2_decompression_test_prepare(this->compr_buf,this->compr_buf_size); + *datalen = orig_slen; + *cdatalen = orig_dlen; + compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen); + this->usecount--; + if (!compr_ret) { + if (jffs2_compression_check) + jffs2_decompression_test(this, data_in, this->compr_buf, *cdatalen, *datalen, this->compr_buf_size); + if (((!best_dlen) || jffs2_is_best_compression(this, best, *cdatalen, best_dlen)) + && (*cdatalen < *datalen)) { + best_dlen = *cdatalen; + best_slen = *datalen; + best = this; + } + } + } + if (best_dlen) { + *cdatalen = best_dlen; + *datalen = best_slen; + output_buf = best->compr_buf; + best->compr_buf = NULL; + best->compr_buf_size = 0; + best->stat_compr_blocks++; + best->stat_compr_orig_size += best_slen; + best->stat_compr_new_size += best_dlen; + ret = best->compr; + } + break; + default: + fprintf(stderr,"mkfs.jffs2: unknown compression mode.\n"); + } +out: + if (ret == JFFS2_COMPR_NONE) { + *cpage_out = data_in; + *datalen = *cdatalen; + none_stat_compr_blocks++; + none_stat_compr_size += *datalen; + } + else { + *cpage_out = output_buf; + } + return ret; +} + + +int jffs2_register_compressor(struct jffs2_compressor *comp) +{ + struct jffs2_compressor *this; + + if (!comp->name) { + fprintf(stderr,"NULL compressor name at registering JFFS2 compressor. Failed.\n"); + return -1; + } + comp->compr_buf_size=0; + comp->compr_buf=NULL; + comp->usecount=0; + comp->stat_compr_orig_size=0; + comp->stat_compr_new_size=0; + comp->stat_compr_blocks=0; + comp->stat_decompr_blocks=0; + + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (this->priority < comp->priority) { + list_add(&comp->list, this->list.prev); + goto out; + } + } + list_add_tail(&comp->list, &jffs2_compressor_list); +out: + return 0; +} + +int jffs2_unregister_compressor(struct jffs2_compressor *comp) +{ + + if (comp->usecount) { + fprintf(stderr,"mkfs.jffs2: Compressor modul is in use. Unregister failed.\n"); + return -1; + } + list_del(&comp->list); + + return 0; +} + +#define JFFS2_STAT_BUF_SIZE 16000 + +char *jffs2_list_compressors(void) +{ + struct jffs2_compressor *this; + char *buf, *act_buf; + + act_buf = buf = malloc(JFFS2_STAT_BUF_SIZE); + list_for_each_entry(this, &jffs2_compressor_list, list) { + act_buf += sprintf(act_buf, "%10s priority:%d ", this->name, this->priority); + if ((this->disabled)||(!this->compress)) + act_buf += sprintf(act_buf,"disabled"); + else + act_buf += sprintf(act_buf,"enabled"); + act_buf += sprintf(act_buf,"\n"); + } + return buf; +} + +char *jffs2_stats(void) +{ + struct jffs2_compressor *this; + char *buf, *act_buf; + + act_buf = buf = malloc(JFFS2_STAT_BUF_SIZE); + + act_buf += sprintf(act_buf,"Compression mode: "); + switch (jffs2_compression_mode) { + case JFFS2_COMPR_MODE_NONE: + act_buf += sprintf(act_buf,"none"); + break; + case JFFS2_COMPR_MODE_PRIORITY: + act_buf += sprintf(act_buf,"priority"); + break; + case JFFS2_COMPR_MODE_SIZE: + act_buf += sprintf(act_buf,"size"); + break; + case JFFS2_COMPR_MODE_FAVOURLZO: + act_buf += sprintf(act_buf, "favourlzo"); + break; + default: + act_buf += sprintf(act_buf, "unknown"); + break; + } + act_buf += sprintf(act_buf,"\nCompressors:\n"); + act_buf += sprintf(act_buf,"%10s ","none"); + act_buf += sprintf(act_buf,"compr: %d blocks (%d) decompr: %d blocks\n", none_stat_compr_blocks, + none_stat_compr_size, none_stat_decompr_blocks); + list_for_each_entry(this, &jffs2_compressor_list, list) { + act_buf += sprintf(act_buf,"%10s (prio:%d) ",this->name,this->priority); + if ((this->disabled)||(!this->compress)) + act_buf += sprintf(act_buf,"- "); + else + act_buf += sprintf(act_buf,"+ "); + act_buf += sprintf(act_buf,"compr: %d blocks (%d/%d) decompr: %d blocks ", this->stat_compr_blocks, + this->stat_compr_new_size, this->stat_compr_orig_size, + this->stat_decompr_blocks); + act_buf += sprintf(act_buf,"\n"); + } + return buf; +} + +int jffs2_set_compression_mode_name(const char *name) +{ + if (!strcmp("none",name)) { + jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; + return 0; + } + if (!strcmp("priority",name)) { + jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; + return 0; + } + if (!strcmp("size",name)) { + jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; + return 0; + } + if (!strcmp("favourlzo", name)) { + jffs2_compression_mode = JFFS2_COMPR_MODE_FAVOURLZO; + return 0; + } + + return 1; +} + +static int jffs2_compressor_Xable(const char *name, int disabled) +{ + struct jffs2_compressor *this; + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (!strcmp(this->name, name)) { + this->disabled = disabled; + return 0; + } + } + return 1; +} + +int jffs2_enable_compressor_name(const char *name) +{ + return jffs2_compressor_Xable(name, 0); +} + +int jffs2_disable_compressor_name(const char *name) +{ + return jffs2_compressor_Xable(name, 1); +} + +int jffs2_set_compressor_priority(const char *name, int priority) +{ + struct jffs2_compressor *this,*comp; + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (!strcmp(this->name, name)) { + this->priority = priority; + comp = this; + goto reinsert; + } + } + fprintf(stderr,"mkfs.jffs2: compressor %s not found.\n",name); + return 1; +reinsert: + /* list is sorted in the order of priority, so if + we change it we have to reinsert it into the + good place */ + list_del(&comp->list); + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (this->priority < comp->priority) { + list_add(&comp->list, this->list.prev); + return 0; + } + } + list_add_tail(&comp->list, &jffs2_compressor_list); + return 0; +} + + +int jffs2_compressors_init(void) +{ +#ifdef CONFIG_JFFS2_ZLIB + jffs2_zlib_init(); +#endif +#ifdef CONFIG_JFFS2_RTIME + jffs2_rtime_init(); +#endif +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_init(); +#endif + return 0; +} + +int jffs2_compressors_exit(void) +{ +#ifdef CONFIG_JFFS2_RTIME + jffs2_rtime_exit(); +#endif +#ifdef CONFIG_JFFS2_ZLIB + jffs2_zlib_exit(); +#endif +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_exit(); +#endif + return 0; +} |