diff options
Diffstat (limited to 'src/execute.c')
| -rw-r--r-- | src/execute.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/src/execute.c b/src/execute.c new file mode 100644 index 0000000..5ad5cc0 --- /dev/null +++ b/src/execute.c @@ -0,0 +1,324 @@ +/* + * bbe - Binary block editor + * + * Copyright (C) 2005 Timo Savinen + * This file is part of bbe. + * + * bbe is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * bbe is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with bbe; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + */ + +/* $Id: execute.c,v 1.12 2005/09/14 17:34:44 timo Exp $ */ + +#include "bbe.h" +#include <stdlib.h> +#include <error.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <string.h> + +/* tells if current byte should be deleted */ +static int delete_this_byte; + +/* tells if current block should be deleted */ +static int delete_this_block; + +/* command list for write_w_command */ +static struct command *current_commands; + +/* commands to be executed at start of buffer */ +/* note J and L must be in every string becaus ethey affect the whole block */ +#define BLOCK_START_COMMANDS "DAJL" + +/* commands to be executed for each byte */ +#define BYTE_COMMANDS "acdirsywjlJL" + +/* commands to be executed at end of buffer */ +#define BLOCK_END_COMMANDS "IJL" + +/* execute given commands */ +void +execute_commands(struct command *c,char *command_letters) +{ + register int i; + unsigned char a,b; + + while(c != NULL) + { + if(strchr(command_letters,c->letter) != NULL) + { + switch(c->letter) + { + case 'A': + case 'I': + write_buffer(c->s1,c->s1_len); + break; + case 'd': + if(c->rpos || c->offset == in_buffer.block_offset) + { + if(c->rpos < c->count) + { + delete_this_byte = 1; + c->rpos++; + } else + { + c->rpos = 0; + } + } + break; + case 'D': + if(c->offset == in_buffer.block_num || c->offset == 0) delete_this_block = 1; + break; + case 'i': + if(c->offset == in_buffer.block_offset) + { + if (!delete_this_byte) write_next_byte(); + write_buffer(c->s1,c->s1_len); + reverse_bytes(1); + } + break; + case 'r': + if(c->offset == in_buffer.block_offset) + { + put_byte(c->s1[0]); + c->rpos=1; + delete_this_byte = 0; + } else if(c->rpos) + { + if(c->rpos < c->s1_len) + { + put_byte(c->s1[c->rpos]); + c->rpos++; + delete_this_byte = 0; + } else + { + c->rpos = 0; + } + } + break; + case 's': + if(delete_this_byte || out_buffer.block_offset + 1 < c->s1_len) break; + i = 0; + while(out_buffer.write_pos[i - c->s1_len + 1] == c->s1[i] && i < c->s1_len) i++; + if(i < c->s1_len) break; + reverse_bytes(c->s1_len - 1); + if(c->s2_len) + { + write_buffer(c->s2,c->s2_len); + reverse_bytes(1); + } else + { + delete_this_byte = 1; + } + break; + case 'y': + i = 0; + while(c->s1[i] != read_byte() && i < c->s1_len) i++; + if(c->s1[i] == read_byte() && i < c->s1_len) put_byte(c->s2[i]); + break; + case 'c': + switch(c->s1[0]) + { + case 'A': // from ascii + switch(c->s1[3]) + { + case 'B': // to bcd + if(c->rpos || (last_byte() && out_buffer.block_offset == 0)) // skip first nibble + { + c->rpos = 0; + if(last_byte()) // unless last byte of block + { + if(*out_buffer.write_pos >= '0' && *out_buffer.write_pos <= '9') + { + a = *out_buffer.write_pos - '0'; + a = (a << 4) & 0xf0; + b = 0x0f; + *out_buffer.write_pos = a | b; + } + } + break; + } + if(out_buffer.block_offset == 0 || delete_this_byte) break; + if((out_buffer.write_pos[-1] >= '0' && out_buffer.write_pos[-1] <= '9')) + { + a = out_buffer.write_pos[-1] - '0'; + a = (a << 4) & 0xf0; + if(*out_buffer.write_pos >= '0' && *out_buffer.write_pos <= '9') + { + b = *out_buffer.write_pos - '0'; + b &= 0x0f; + delete_this_byte = 1; + c->rpos = 1; + } else + { + b = 0x0f; + } + out_buffer.write_pos[-1] = a | b; + } + break; + } + break; + case 'B': // from bcd + switch(c->s1[3]) + { + case 'A': // to ascii + if(((*out_buffer.write_pos >> 4) & 0x0f) <= 9 && + ((*out_buffer.write_pos & 0x0f) <= 9 || (*out_buffer.write_pos & 0x0f) == 0x0f)) + { + a = (*out_buffer.write_pos >> 4) & 0x0f; + b = *out_buffer.write_pos & 0x0f; + *out_buffer.write_pos = '0' + a; + if(!delete_this_byte && b != 0x0f) + { + write_next_byte(); + *out_buffer.write_pos = '0' + b; + } + } + break; + } + break; + } + break; + case 'j': + if(in_buffer.block_offset < c->count) + { + while(c->next != NULL) c = c->next; // skip rest of commands + } + break; + case 'J': + if(in_buffer.block_num <= c->count) + { + while(c->next != NULL) c = c->next; // skip rest of commands + } + break; + case 'l': + if(in_buffer.block_offset >= c->count) + { + while(c->next != NULL) c = c->next; // skip rest of commands + } + break; + case 'L': + if(in_buffer.block_num > c->count) + { + while(c->next != NULL) c = c->next; // skip rest of commands + } + break; + case 'w': + break; + } + } + c = c->next; + } +} + +/* write w command, will be called when output_buffer is written, same will be written to w-command files */ +void +write_w_command(unsigned char *buf,size_t length) +{ + struct command *c; + + c = current_commands; + + while(c != NULL) + { + if(c->letter == 'w') + { + if(fwrite(buf,1,length,c->fd) != length) panic("Cannot write to file",c->s1,strerror(errno)); + } + c = c->next; + } +} + + + +/* init_commands, initialize those wich need it, currently w - open file and rpos=0 for all */ +void +init_commands(struct command *c) +{ + while(c != NULL) + { + switch(c->letter) + { + case 'w': + c->fd = fopen(c->s1,"w"); + if(c->fd == NULL) panic("Cannot open file for writing",c->s1,strerror(errno)); + break; + } + c = c->next; + } +} + + +/* close_commands, close those wich need it, currently w - close file */ +void +close_commands(struct command *c) +{ + while(c != NULL) + { + switch(c->letter) + { + case 'w': + if(fclose(c->fd) != 0) panic("Error in closing file",c->s1,strerror(errno)); + break; + } + c = c->next; + } +} + +/* reset the rpos counter for next block, in case block was shorter eg. delete count */ +inline void +reset_rpos(struct command *c) +{ + while(c != NULL) + { + c->rpos = 0; + c = c->next; + } +} + + + +/* main execution loop */ +void +execute_program(struct command *c) +{ + int block_end; + + current_commands = c; + + while(find_block()) + { + delete_this_block = 0; + reset_rpos(c); + execute_commands(c,BLOCK_START_COMMANDS); + out_buffer.block_offset = 0; + do + { + set_cycle_start(); + delete_this_byte = 0; + block_end = last_byte(); + put_byte(read_byte()); // as default write current byte from input + execute_commands(c,BYTE_COMMANDS); + if(!delete_this_byte && !delete_this_block) + { + write_next_byte(); // advance the write pointer if byte is not marked for del + } + if(!block_end) get_next_byte(); + } while (!block_end); + execute_commands(c,BLOCK_END_COMMANDS); + flush_buffer(); + } + close_output_stream(); +} |
