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busybox/editors/sed.c
Eric Andersen 52a3c2726e Patch from Matt Kraai: 
sed is broken:

 busybox sed -n '/^a/,/^a/p' >output <<EOF
 a
 b
 a
 b
 EOF
 cmp -s output - <<EOF
 a
 b
 a
 EOF

The attached patch fixes it.
2003-12-23 08:53:51 +00:00

1142 lines
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/* vi: set sw=4 ts=4: */
/*
* sed.c - very minimalist version of sed
*
* Copyright (C) 1999,2000,2001 by Lineo, inc. and Mark Whitley
* Copyright (C) 1999,2000,2001 by Mark Whitley <markw@codepoet.org>
* Copyright (C) 2002 Matt Kraai
* Copyright (C) 2003 by Glenn McGrath <bug1@optushome.com.au>
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/* Code overview.
Files are laid out to avoid unnecessary function declarations. So for
example, every function add_cmd calls occurs before add_cmd in this file.
add_cmd() is called on each line of sed command text (from a file or from
the command line). It calls get_address() and parse_cmd_args(). The
resulting sed_cmd_t structures are appended to a linked list
(sed_cmd_head/sed_cmd_tail).
process_file() does actual sedding, reading data lines from an input FILE *
(which could be stdin) and applying the sed command list (sed_cmd_head) to
each of the resulting lines.
sed_main() is where external code calls into this, with a command line.
*/
/*
Supported features and commands in this version of sed:
- comments ('#')
- address matching: num|/matchstr/[,num|/matchstr/|$]command
- commands: (p)rint, (d)elete, (s)ubstitue (with g & I flags)
- edit commands: (a)ppend, (i)nsert, (c)hange
- file commands: (r)ead
- backreferences in substitution expressions (\1, \2...\9)
- grouped commands: {cmd1;cmd2}
- transliteration (y/source-chars/dest-chars/)
- pattern space hold space storing / swapping (g, h, x)
- labels / branching (: label, b, t)
(Note: Specifying an address (range) to match is *optional*; commands
default to the whole pattern space if no specific address match was
requested.)
Unsupported features:
- GNU extensions
- and more.
Todo:
- Create a wrapper around regex to make libc's regex conform with sed
- Fix bugs
Reference http://www.opengroup.org/onlinepubs/007904975/utilities/sed.html
*/
#include <stdio.h>
#include <unistd.h> /* for getopt() */
#include <regex.h>
#include <string.h> /* for strdup() */
#include <errno.h>
#include <ctype.h> /* for isspace() */
#include <stdlib.h>
#include "busybox.h"
typedef struct sed_cmd_s {
/* Ordered by alignment requirements: currently 36 bytes on x86 */
/* address storage */
regex_t *beg_match; /* sed -e '/match/cmd' */
regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */
regex_t *sub_match; /* For 's/sub_match/string/' */
int beg_line; /* 'sed 1p' 0 == apply commands to all lines */
int end_line; /* 'sed 1,3p' 0 == one line only. -1 = last line ($) */
FILE *file; /* File (sr) command writes to, -1 for none. */
char *string; /* Data string for (saicytb) commands. */
unsigned short which_match; /* (s) Which match to replace (0 for all) */
/* Bitfields (gcc won't group them if we don't) */
unsigned int invert:1; /* the '!' after the address */
unsigned int in_match:1; /* Next line also included in match? */
unsigned int no_newline:1; /* Last line written by (sr) had no '\n' */
unsigned int sub_p:1; /* (s) print option */
/* GENERAL FIELDS */
char cmd; /* The command char: abcdDgGhHilnNpPqrstwxy:={} */
struct sed_cmd_s *next; /* Next command (linked list, NULL terminated) */
} sed_cmd_t;
/* globals */
/* options */
static int be_quiet = 0;
static const char bad_format_in_subst[] =
"bad format in substitution expression";
const char *const semicolon_whitespace = "; \n\r\t\v";
regmatch_t regmatch[10];
static regex_t *previous_regex_ptr = NULL;
/* linked list of sed commands */
static sed_cmd_t sed_cmd_head;
static sed_cmd_t *sed_cmd_tail = &sed_cmd_head;
/* Linked list of append lines */
struct append_list {
char *string;
struct append_list *next;
};
struct append_list *append_head=NULL, *append_tail=NULL;
#ifdef CONFIG_FEATURE_CLEAN_UP
static void free_and_close_stuff(void)
{
sed_cmd_t *sed_cmd = sed_cmd_head.next;
while(append_head) {
append_tail=append_head->next;
free(append_head->string);
free(append_head);
append_head=append_tail;
}
while (sed_cmd) {
sed_cmd_t *sed_cmd_next = sed_cmd->next;
if(sed_cmd->file)
bb_xprint_and_close_file(sed_cmd->file);
if (sed_cmd->beg_match) {
regfree(sed_cmd->beg_match);
free(sed_cmd->beg_match);
}
if (sed_cmd->end_match) {
regfree(sed_cmd->end_match);
free(sed_cmd->end_match);
}
if (sed_cmd->sub_match) {
regfree(sed_cmd->sub_match);
free(sed_cmd->sub_match);
}
free(sed_cmd->string);
free(sed_cmd);
sed_cmd = sed_cmd_next;
}
}
#endif
/* strdup, replacing "\n" with '\n', and "\delimiter" with 'delimiter' */
static void parse_escapes(char *dest, const char *string, int len, char from, char to)
{
int i=0;
while(i<len) {
if(string[i] == '\\') {
if(!to || string[i+1] == from) {
*(dest++) = to ? to : string[i+1];
i+=2;
continue;
} else *(dest++)=string[i++];
}
*(dest++) = string[i++];
}
*dest=0;
}
static char *copy_parsing_slashn(const char *string, int len)
{
char *dest=xmalloc(len+1);
parse_escapes(dest,string,len,'n','\n');
return dest;
}
/*
* index_of_next_unescaped_regexp_delim - walks left to right through a string
* beginning at a specified index and returns the index of the next regular
* expression delimiter (typically a forward * slash ('/')) not preceeded by
* a backslash ('\').
*/
static int index_of_next_unescaped_regexp_delim(const char delimiter,
const char *str)
{
int bracket = -1;
int escaped = 0;
int idx = 0;
char ch;
for (; (ch = str[idx]); idx++) {
if (bracket != -1) {
if (ch == ']' && !(bracket == idx - 1 || (bracket == idx - 2
&& str[idx - 1] == '^')))
bracket = -1;
} else if (escaped)
escaped = 0;
else if (ch == '\\')
escaped = 1;
else if (ch == '[')
bracket = idx;
else if (ch == delimiter)
return idx;
}
/* if we make it to here, we've hit the end of the string */
return -1;
}
/*
* Returns the index of the third delimiter
*/
static int parse_regex_delim(const char *cmdstr, char **match, char **replace)
{
const char *cmdstr_ptr = cmdstr;
char delimiter;
int idx = 0;
/* verify that the 's' or 'y' is followed by something. That something
* (typically a 'slash') is now our regexp delimiter... */
if (*cmdstr == '\0') bb_error_msg_and_die(bad_format_in_subst);
delimiter = *(cmdstr_ptr++);
/* save the match string */
idx = index_of_next_unescaped_regexp_delim(delimiter, cmdstr_ptr);
if (idx == -1) {
bb_error_msg_and_die(bad_format_in_subst);
}
*match = copy_parsing_slashn(cmdstr_ptr, idx);
/* save the replacement string */
cmdstr_ptr += idx + 1;
idx = index_of_next_unescaped_regexp_delim(delimiter, cmdstr_ptr);
if (idx == -1) {
bb_error_msg_and_die(bad_format_in_subst);
}
*replace = copy_parsing_slashn(cmdstr_ptr, idx);
return ((cmdstr_ptr - cmdstr) + idx);
}
/*
* returns the index in the string just past where the address ends.
*/
static int get_address(char *my_str, int *linenum, regex_t ** regex)
{
char *pos = my_str;
if (isdigit(*my_str)) {
*linenum = strtol(my_str, &pos, 10);
/* endstr shouldnt ever equal NULL */
} else if (*my_str == '$') {
*linenum = -1;
pos++;
} else if (*my_str == '/' || *my_str == '\\') {
int next;
char delimiter;
char *temp;
if (*my_str == '\\') delimiter = *(++pos);
else delimiter = '/';
next = index_of_next_unescaped_regexp_delim(delimiter, ++pos);
if (next == -1)
bb_error_msg_and_die("unterminated match expression");
temp=copy_parsing_slashn(pos,next);
*regex = (regex_t *) xmalloc(sizeof(regex_t));
xregcomp(*regex, temp, REG_NEWLINE);
free(temp);
/* Move position to next character after last delimiter */
pos+=(next+1);
}
return pos - my_str;
}
/* Grab a filename. Whitespace at start is skipped, then goes to EOL. */
static int parse_file_cmd(sed_cmd_t * sed_cmd, const char *filecmdstr, char **retval)
{
int start = 0, idx, hack=0;
/* Skip whitespace, then grab filename to end of line */
while (isspace(filecmdstr[start])) start++;
idx=start;
while(filecmdstr[idx] && filecmdstr[idx]!='\n') idx++;
/* If lines glued together, put backslash back. */
if(filecmdstr[idx]=='\n') hack=1;
if(idx==start) bb_error_msg_and_die("Empty filename");
*retval = bb_xstrndup(filecmdstr+start, idx-start+hack+1);
if(hack) *(idx+*retval)='\\';
return idx;
}
static int parse_subst_cmd(sed_cmd_t * const sed_cmd, char *substr)
{
int cflags = 0;
char *match;
int idx = 0;
/*
* A substitution command should look something like this:
* s/match/replace/ #gIpw
* || | |||
* mandatory optional
*/
idx = parse_regex_delim(substr, &match, &sed_cmd->string);
/* determine the number of back references in the match string */
/* Note: we compute this here rather than in the do_subst_command()
* function to save processor time, at the expense of a little more memory
* (4 bits) per sed_cmd */
/* process the flags */
sed_cmd->which_match=1;
while (substr[++idx]) {
/* Parse match number */
if(isdigit(substr[idx])) {
if(match[0]!='^') {
/* Match 0 treated as all, multiple matches we take the last one. */
char *pos=substr+idx;
sed_cmd->which_match=(unsigned short)strtol(substr+idx,&pos,10);
idx=pos-substr;
}
/* Skip spaces */
if(isspace(substr[idx])) continue;
continue;
}
switch (substr[idx]) {
/* Replace all occurrences */
case 'g':
if (match[0] != '^') sed_cmd->which_match = 0;
break;
/* Print pattern space */
case 'p':
sed_cmd->sub_p = 1;
break;
case 'w':
{
char *temp;
idx+=parse_file_cmd(sed_cmd,substr+idx,&temp);
break;
}
/* Ignore case (gnu exension) */
case 'I':
cflags |= REG_ICASE;
break;
case ';':
case '}':
goto out;
default:
bb_error_msg_and_die("bad option in substitution expression");
}
}
out:
/* compile the match string into a regex */
if (*match != '\0') {
/* If match is empty, we use last regex used at runtime */
sed_cmd->sub_match = (regex_t *) xmalloc(sizeof(regex_t));
xregcomp(sed_cmd->sub_match, match, cflags);
}
free(match);
return idx;
}
/*
* Process the commands arguments
*/
static char *parse_cmd_args(sed_cmd_t *sed_cmd, char *cmdstr)
{
/* handle (s)ubstitution command */
if (sed_cmd->cmd == 's') cmdstr += parse_subst_cmd(sed_cmd, cmdstr);
/* handle edit cmds: (a)ppend, (i)nsert, and (c)hange */
else if (strchr("aic", sed_cmd->cmd)) {
if ((sed_cmd->end_line || sed_cmd->end_match) && sed_cmd->cmd != 'c')
bb_error_msg_and_die
("only a beginning address can be specified for edit commands");
while(isspace(*cmdstr)) cmdstr++;
sed_cmd->string = bb_xstrdup(cmdstr);
parse_escapes(sed_cmd->string,sed_cmd->string,strlen(cmdstr),0,0);
cmdstr += strlen(cmdstr);
/* handle file cmds: (r)ead */
} else if(strchr("rw", sed_cmd->cmd)) {
if (sed_cmd->end_line || sed_cmd->end_match)
bb_error_msg_and_die("Command only uses one address");
cmdstr += parse_file_cmd(sed_cmd, cmdstr, &sed_cmd->string);
if(sed_cmd->cmd=='w')
sed_cmd->file=bb_xfopen(sed_cmd->string,"w");
/* handle branch commands */
} else if (strchr(":bt", sed_cmd->cmd)) {
int length;
while(isspace(*cmdstr)) cmdstr++;
length = strcspn(cmdstr, semicolon_whitespace);
if (length) {
sed_cmd->string = strndup(cmdstr, length);
cmdstr += length;
}
}
/* translation command */
else if (sed_cmd->cmd == 'y') {
char *match, *replace;
int i=cmdstr[0];
cmdstr+=parse_regex_delim(cmdstr, &match, &replace)+1;
/* \n already parsed, but \delimiter needs unescaping. */
parse_escapes(match,match,strlen(match),i,i);
parse_escapes(replace,replace,strlen(replace),i,i);
sed_cmd->string = xcalloc(1, (strlen(match) + 1) * 2);
for (i = 0; match[i] && replace[i]; i++) {
sed_cmd->string[i * 2] = match[i];
sed_cmd->string[(i * 2) + 1] = replace[i];
}
free(match);
free(replace);
}
/* if it wasnt a single-letter command that takes no arguments
* then it must be an invalid command.
*/
else if (strchr("dDgGhHlnNpPqx={}", sed_cmd->cmd) == 0) {
bb_error_msg_and_die("Unsupported command %c", sed_cmd->cmd);
}
/* give back whatever's left over */
return (cmdstr);
}
/* Parse address+command sets, skipping comment lines. */
void add_cmd(char *cmdstr)
{
static char *add_cmd_line=NULL;
sed_cmd_t *sed_cmd;
int temp;
/* Append this line to any unfinished line from last time. */
if(add_cmd_line) {
int lastlen=strlen(add_cmd_line);
char *tmp=xmalloc(lastlen+strlen(cmdstr)+2);
memcpy(tmp,add_cmd_line,lastlen);
tmp[lastlen]='\n';
strcpy(tmp+lastlen+1,cmdstr);
free(add_cmd_line);
cmdstr=add_cmd_line=tmp;
} else add_cmd_line=NULL;
/* If this line ends with backslash, request next line. */
temp=strlen(cmdstr);
if(temp && cmdstr[temp-1]=='\\') {
if(!add_cmd_line) add_cmd_line=strdup(cmdstr);
add_cmd_line[temp-1]=0;
return;
}
/* Loop parsing all commands in this line. */
while(*cmdstr) {
/* Skip leading whitespace and semicolons */
cmdstr += strspn(cmdstr, semicolon_whitespace);
/* If no more commands, exit. */
if(!*cmdstr) break;
/* if this is a comment, jump past it and keep going */
if (*cmdstr == '#') {
/* "#n" is the same as using -n on the command line */
if (cmdstr[1] == 'n') be_quiet++;
if(!(cmdstr=strpbrk(cmdstr, "\n\r"))) break;
continue;
}
/* parse the command
* format is: [addr][,addr][!]cmd
* |----||-----||-|
* part1 part2 part3
*/
sed_cmd = xcalloc(1, sizeof(sed_cmd_t));
/* first part (if present) is an address: either a '$', a number or a /regex/ */
cmdstr += get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match);
/* second part (if present) will begin with a comma */
if (*cmdstr == ',') {
int idx;
cmdstr++;
idx = get_address(cmdstr, &sed_cmd->end_line, &sed_cmd->end_match);
if (!idx) bb_error_msg_and_die("get_address: no address found in string\n");
cmdstr += idx;
}
/* skip whitespace before the command */
while (isspace(*cmdstr)) cmdstr++;
/* Check for inversion flag */
if (*cmdstr == '!') {
sed_cmd->invert = 1;
cmdstr++;
/* skip whitespace before the command */
while (isspace(*cmdstr)) cmdstr++;
}
/* last part (mandatory) will be a command */
if (!*cmdstr) bb_error_msg_and_die("missing command");
sed_cmd->cmd = *(cmdstr++);
cmdstr = parse_cmd_args(sed_cmd, cmdstr);
/* Add the command to the command array */
sed_cmd_tail->next = sed_cmd;
sed_cmd_tail = sed_cmd_tail->next;
}
/* If we glued multiple lines together, free the memory. */
if(add_cmd_line) {
free(add_cmd_line);
add_cmd_line=NULL;
}
}
struct pipeline {
char *buf; /* Space to hold string */
int idx; /* Space used */
int len; /* Space allocated */
} pipeline;
#define PIPE_GROW 64
void pipe_putc(char c)
{
if(pipeline.idx==pipeline.len) {
pipeline.buf = xrealloc(pipeline.buf, pipeline.len + PIPE_GROW);
pipeline.len+=PIPE_GROW;
}
pipeline.buf[pipeline.idx++] = (c);
}
static void do_subst_w_backrefs(const char *line, const char *replace)
{
int i,j;
/* go through the replacement string */
for (i = 0; replace[i]; i++) {
/* if we find a backreference (\1, \2, etc.) print the backref'ed * text */
if (replace[i] == '\\' && replace[i+1]>'0' && replace[i+1]<='9') {
int backref=replace[++i]-'0';
/* print out the text held in regmatch[backref] */
if(regmatch[backref].rm_so != -1)
for (j = regmatch[backref].rm_so; j < regmatch[backref].rm_eo; j++)
pipe_putc(line[j]);
}
/* if we find a backslash escaped character, print the character */
else if (replace[i] == '\\') pipe_putc(replace[++i]);
/* if we find an unescaped '&' print out the whole matched text. */
else if (replace[i] == '&')
for (j = regmatch[0].rm_so; j < regmatch[0].rm_eo; j++)
pipe_putc(line[j]);
/* Otherwise just output the character. */
else pipe_putc(replace[i]);
}
}
static int do_subst_command(sed_cmd_t * sed_cmd, char **line)
{
char *oldline = *line;
int altered = 0;
int match_count=0;
regex_t *current_regex;
/* Handle empty regex. */
if (sed_cmd->sub_match == NULL) {
current_regex = previous_regex_ptr;
if(!current_regex)
bb_error_msg_and_die("No previous regexp.");
} else previous_regex_ptr = current_regex = sed_cmd->sub_match;
/* Find the first match */
if(REG_NOMATCH==regexec(current_regex, oldline, 10, regmatch, 0))
return 0;
/* Initialize temporary output buffer. */
pipeline.buf=xmalloc(PIPE_GROW);
pipeline.len=PIPE_GROW;
pipeline.idx=0;
/* Now loop through, substituting for matches */
do {
int i;
match_count++;
/* If we aren't interested in this match, output old line to
end of match and continue */
if(sed_cmd->which_match && sed_cmd->which_match!=match_count) {
for(i=0;i<regmatch[0].rm_eo;i++)
pipe_putc(oldline[i]);
continue;
}
/* print everything before the match */
for (i = 0; i < regmatch[0].rm_so; i++) pipe_putc(oldline[i]);
/* then print the substitution string */
do_subst_w_backrefs(oldline, sed_cmd->string);
/* advance past the match */
oldline += regmatch[0].rm_eo;
/* flag that something has changed */
altered++;
/* if we're not doing this globally, get out now */
if (sed_cmd->which_match) break;
} while (*oldline && (regexec(current_regex, oldline, 10, regmatch, 0) != REG_NOMATCH));
/* Copy rest of string into output pipeline */
while(*oldline) pipe_putc(*(oldline++));
pipe_putc(0);
free(*line);
*line = pipeline.buf;
return altered;
}
/* Set command pointer to point to this label. (Does not handle null label.) */
static sed_cmd_t *branch_to(const char *label)
{
sed_cmd_t *sed_cmd;
for (sed_cmd = sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) {
if ((sed_cmd->cmd == ':') && (sed_cmd->string) && (strcmp(sed_cmd->string, label) == 0)) {
return (sed_cmd);
}
}
bb_error_msg_and_die("Can't find label for jump to `%s'", label);
}
/* Append copy of string to append buffer */
static void append(char *s)
{
struct append_list *temp=calloc(1,sizeof(struct append_list));
if(append_head)
append_tail=(append_tail->next=temp);
else append_head=append_tail=temp;
temp->string=strdup(s);
}
static void flush_append(void)
{
/* Output appended lines. */
while(append_head) {
puts(append_head->string);
append_tail=append_head->next;
free(append_head->string);
free(append_head);
append_head=append_tail;
}
append_head=append_tail=NULL;
}
/* Get next line of input, flushing append buffer and noting if we hit EOF
* without a newline on the last line.
*/
static char *get_next_line(FILE * file, int *no_newline)
{
char *temp;
int len;
flush_append();
temp=bb_get_line_from_file(file);
if(temp) {
len=strlen(temp);
if(len && temp[len-1]=='\n') temp[len-1]=0;
else *no_newline=1;
}
return temp;
}
/* Output line of text. missing_newline means the last line output did not
end with a newline. no_newline means this line does not end with a
newline. */
static int puts_maybe_newline(char *s, FILE *file, int missing_newline, int no_newline)
{
if(missing_newline) fputc('\n',file);
fputs(s,file);
if(!no_newline) fputc('\n',file);
return no_newline;
}
#define sed_puts(s,n) missing_newline=puts_maybe_newline(s,stdout,missing_newline,n)
static void process_file(FILE * file)
{
char *pattern_space, *next_line, *hold_space=NULL;
static int linenum = 0, missing_newline=0;
int no_newline,next_no_newline=0;
next_line = get_next_line(file,&next_no_newline);
/* go through every line in the file */
for(;;) {
sed_cmd_t *sed_cmd;
int substituted=0;
/* Advance to next line. Stop if out of lines. */
if(!(pattern_space=next_line)) break;
no_newline=next_no_newline;
/* Read one line in advance so we can act on the last line, the '$' address */
next_line = get_next_line(file,&next_no_newline);
linenum++;
restart:
/* for every line, go through all the commands */
for (sed_cmd = sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) {
int old_matched, matched;
old_matched = sed_cmd->in_match;
/* Determine if this command matches this line: */
/* Are we continuing a previous multi-line match? */
sed_cmd->in_match = sed_cmd->in_match
/* Or is no range necessary? */
|| (!sed_cmd->beg_line && !sed_cmd->end_line
&& !sed_cmd->beg_match && !sed_cmd->end_match)
/* Or did we match the start of a numerical range? */
|| (sed_cmd->beg_line > 0 && (sed_cmd->beg_line == linenum))
/* Or does this line match our begin address regex? */
|| (sed_cmd->beg_match &&
!regexec(sed_cmd->beg_match, pattern_space, 0, NULL, 0))
/* Or did we match last line of input? */
|| (sed_cmd->beg_line == -1 && next_line == NULL);
/* Snapshot the value */
matched = sed_cmd->in_match;
/* Is this line the end of the current match? */
if(matched) {
sed_cmd->in_match = !(
/* has the ending line come, or is this a single address command? */
(sed_cmd->end_line ?
sed_cmd->end_line==-1 ?
!next_line
: sed_cmd->end_line<=linenum
: !sed_cmd->end_match)
/* or does this line matches our last address regex */
|| (sed_cmd->end_match && old_matched && (regexec(sed_cmd->end_match, pattern_space, 0, NULL, 0) == 0))
);
}
/* Skip blocks of commands we didn't match. */
if (sed_cmd->cmd == '{') {
if(sed_cmd->invert ? matched : !matched)
while(sed_cmd && sed_cmd->cmd!='}') sed_cmd=sed_cmd->next;
if(!sed_cmd) bb_error_msg_and_die("Unterminated {");
continue;
}
/* Okay, so did this line match? */
if (sed_cmd->invert ? !matched : matched) {
/* Update last used regex in case a blank substitute BRE is found */
if (sed_cmd->beg_match) {
previous_regex_ptr = sed_cmd->beg_match;
}
/* actual sedding */
switch (sed_cmd->cmd) {
/* Print line number */
case '=':
printf("%d\n", linenum);
break;
/* Write the current pattern space up to the first newline */
case 'P':
{
char *tmp = strchr(pattern_space, '\n');
if (tmp) {
*tmp = '\0';
sed_puts(pattern_space,1);
*tmp = '\n';
break;
}
/* Fall Through */
}
/* Write the current pattern space to output */
case 'p':
sed_puts(pattern_space,no_newline);
break;
/* Delete up through first newline */
case 'D':
{
char *tmp = strchr(pattern_space,'\n');
if(tmp) {
tmp=bb_xstrdup(tmp+1);
free(pattern_space);
pattern_space=tmp;
goto restart;
}
}
/* discard this line. */
case 'd':
goto discard_line;
/* Substitute with regex */
case 's':
if(do_subst_command(sed_cmd, &pattern_space)) {
substituted|=1;
/* handle p option */
if(sed_cmd->sub_p)
sed_puts(pattern_space,no_newline);
/* handle w option */
if(sed_cmd->file)
sed_cmd->no_newline=puts_maybe_newline(pattern_space, sed_cmd->file, sed_cmd->no_newline, no_newline);
}
break;
/* Append line to linked list to be printed later */
case 'a':
{
append(sed_cmd->string);
break;
}
/* Insert text before this line */
case 'i':
sed_puts(sed_cmd->string,1);
break;
/* Cut and paste text (replace) */
case 'c':
/* Only triggers on last line of a matching range. */
if (!sed_cmd->in_match) sed_puts(sed_cmd->string,1);
goto discard_line;
/* Read file, append contents to output */
case 'r':
{
FILE *outfile;
outfile = fopen(sed_cmd->string, "r");
if (outfile) {
char *line;
while ((line = bb_get_chomped_line_from_file(outfile))
!= NULL)
append(line);
bb_xprint_and_close_file(outfile);
}
break;
}
/* Write pattern space to file. */
case 'w':
sed_cmd->no_newline=puts_maybe_newline(pattern_space,sed_cmd->file, sed_cmd->no_newline,no_newline);
break;
/* Read next line from input */
case 'n':
if (!be_quiet)
sed_puts(pattern_space,no_newline);
if (next_line) {
free(pattern_space);
pattern_space = next_line;
no_newline=next_no_newline;
next_line = get_next_line(file,&next_no_newline);
linenum++;
break;
}
/* fall through */
/* Quit. End of script, end of input. */
case 'q':
/* Exit the outer while loop */
free(next_line);
next_line = NULL;
goto discard_commands;
/* Append the next line to the current line */
case 'N':
{
/* If no next line, jump to end of script and exit. */
if (next_line == NULL) {
/* Jump to end of script and exit */
free(next_line);
next_line = NULL;
goto discard_line;
/* append next_line, read new next_line. */
} else {
int len=strlen(pattern_space);
pattern_space = realloc(pattern_space, len + strlen(next_line) + 2);
pattern_space[len]='\n';
strcpy(pattern_space+len+1, next_line);
no_newline=next_no_newline;
next_line = get_next_line(file,&next_no_newline);
linenum++;
}
break;
}
/* Test if substition worked, branch if so. */
case 't':
if (!substituted) break;
substituted=0;
/* Fall through */
/* Branch to label */
case 'b':
if (!sed_cmd->string) goto discard_commands;
else sed_cmd = branch_to(sed_cmd->string);
break;
/* Transliterate characters */
case 'y':
{
int i;
for (i = 0; pattern_space[i]; i++) {
int j;
for (j = 0; sed_cmd->string[j]; j += 2) {
if (pattern_space[i] == sed_cmd->string[j]) {
pattern_space[i] = sed_cmd->string[j + 1];
}
}
}
break;
}
case 'g': /* Replace pattern space with hold space */
free(pattern_space);
if (hold_space) {
pattern_space = strdup(hold_space);
no_newline=0;
}
break;
case 'G': /* Append newline and hold space to pattern space */
{
int pattern_space_size = 2;
int hold_space_size = 0;
if (pattern_space)
pattern_space_size += strlen(pattern_space);
if (hold_space) hold_space_size = strlen(hold_space);
pattern_space = xrealloc(pattern_space, pattern_space_size + hold_space_size);
if (pattern_space_size == 2) pattern_space[0]=0;
strcat(pattern_space, "\n");
if (hold_space) strcat(pattern_space, hold_space);
no_newline=0;
break;
}
case 'h': /* Replace hold space with pattern space */
free(hold_space);
hold_space = strdup(pattern_space);
break;
case 'H': /* Append newline and pattern space to hold space */
{
int hold_space_size = 2;
int pattern_space_size = 0;
if (hold_space) hold_space_size += strlen(hold_space);
if (pattern_space)
pattern_space_size = strlen(pattern_space);
hold_space = xrealloc(hold_space,
hold_space_size + pattern_space_size);
if (hold_space_size == 2) hold_space[0]=0;
strcat(hold_space, "\n");
if (pattern_space) strcat(hold_space, pattern_space);
break;
}
case 'x': /* Exchange hold and pattern space */
{
char *tmp = pattern_space;
pattern_space = hold_space;
no_newline=0;
hold_space = tmp;
break;
}
}
}
}
/*
* exit point from sedding...
*/
discard_commands:
/* we will print the line unless we were told to be quiet ('-n')
or if the line was suppressed (ala 'd'elete) */
if (!be_quiet) sed_puts(pattern_space,no_newline);
/* Delete and such jump here. */
discard_line:
flush_append();
free(pattern_space);
}
}
/* It is possible to have a command line argument with embedded
newlines. This counts as multiple command lines. */
static void add_cmd_block(char *cmdstr)
{
int go=1;
char *temp=bb_xstrdup(cmdstr),*temp2=temp;
while(go) {
int len=strcspn(temp2,"\n");
if(!temp2[len]) go=0;
else temp2[len]=0;
add_cmd(temp2);
temp2+=len+1;
}
free(temp);
}
extern int sed_main(int argc, char **argv)
{
int opt, status = EXIT_SUCCESS;
#ifdef CONFIG_FEATURE_CLEAN_UP
/* destroy command strings on exit */
if (atexit(free_and_close_stuff) == -1)
bb_perror_msg_and_die("atexit");
#endif
/* do normal option parsing */
while ((opt = getopt(argc, argv, "ne:f:")) > 0) {
switch (opt) {
case 'n':
be_quiet++;
break;
case 'e':
add_cmd_block(optarg);
break;
case 'f':
{
FILE *cmdfile;
char *line;
cmdfile = bb_xfopen(optarg, "r");
while ((line = bb_get_chomped_line_from_file(cmdfile))
!= NULL) {
add_cmd(line);
free(line);
}
bb_xprint_and_close_file(cmdfile);
break;
}
default:
bb_show_usage();
}
}
/* if we didn't get a pattern from a -e and no command file was specified,
* argv[optind] should be the pattern. no pattern, no worky */
if (sed_cmd_head.next == NULL) {
if (argv[optind] == NULL)
bb_show_usage();
else
add_cmd_block(argv[optind++]);
}
/* Flush any unfinished commands. */
add_cmd("");
/* argv[(optind)..(argc-1)] should be names of file to process. If no
* files were specified or '-' was specified, take input from stdin.
* Otherwise, we process all the files specified. */
if (argv[optind] == NULL) {
process_file(stdin);
} else {
int i;
FILE *file;
for (i = optind; i < argc; i++) {
if(!strcmp(argv[i], "-")) {
process_file(stdin);
} else {
file = bb_wfopen(argv[i], "r");
if (file) {
process_file(file);
fclose(file);
} else {
status = EXIT_FAILURE;
}
}
}
}
return status;
}
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