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fc4cb4dbb5
busybox/editors/sed.c
Glenn L McGrath fc4cb4dbb5 Fix logic error in grouped commands
2003-04-12 16:10:42 +00:00

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/*
* 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
*
*/
/*
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 lots, lots more.
Bugs:
- Cant subst globally using ^ or $ in regex, eg. "aah" | sed 's/^a/b/g'
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 {
/* Order by alignment requirements */
/* address storage */
regex_t *beg_match; /* sed -e '/match/cmd' */
regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */
int beg_line; /* 'sed 1p' 0 == no begining line, apply commands to all lines */
int end_line; /* 'sed 1,3p' 0 == no end line, use only beginning. -1 == $ */
/* inversion flag */
int invert; /* the '!' after the address */
// int block_cmd; /* This command is part of a group that has a command address */
/* SUBSTITUTION COMMAND SPECIFIC FIELDS */
/* sed -e 's/sub_match/replace/' */
regex_t *sub_match;
char *replace;
/* EDIT COMMAND (a,i,c) SPECIFIC FIELDS */
char *editline;
/* FILE COMMAND (r) SPECIFIC FIELDS */
char *filename;
/* SUBSTITUTION COMMAND SPECIFIC FIELDS */
unsigned int num_backrefs:4; /* how many back references (\1..\9) */
/* Note: GNU/POSIX sed does not save more than nine backrefs, so
* we only use 4 bits to hold the number */
unsigned int sub_g:1; /* sed -e 's/foo/bar/g' (global) */
unsigned int sub_p:1; /* sed -e 's/foo/bar/p' (print substitution) */
/* TRANSLATE COMMAND */
char *translate;
/* GENERAL FIELDS */
/* the command */
char cmd; /* p,d,s (add more at your leisure :-) */
/* Branch commands */
char *label;
/* next command in list (sequential list of specified commands) */
struct sed_cmd_s *next;
} sed_cmd_t;
/* externs */
extern void xregcomp(regex_t * preg, const char *regex, int cflags);
extern int optind; /* in unistd.h */
extern char *optarg; /* ditto */
/* globals */
/* options */
static int be_quiet = 0;
static const char bad_format_in_subst[] =
"bad format in substitution expression";
/* linked list of sed commands */
static sed_cmd_t sed_cmd_head;
static sed_cmd_t *sed_cmd_tail = &sed_cmd_head;
const char *const semicolon_whitespace = "; \n\r\t\v\0";
static regex_t *previous_regex_ptr = NULL;
#ifdef CONFIG_FEATURE_CLEAN_UP
static void destroy_cmd_strs(void)
{
sed_cmd_t *sed_cmd = sed_cmd_head.next;
while (sed_cmd) {
sed_cmd_t *sed_cmd_next = sed_cmd->next;
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->replace);
free(sed_cmd);
sed_cmd = sed_cmd_next;
}
}
#endif
/*
* 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;
}
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' 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);
else
delimiter = *cmdstr_ptr;
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 = bb_xstrndup(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 = bb_xstrndup(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)
{
int idx = 0;
if (isdigit(my_str[idx])) {
char *endstr;
*linenum = strtol(my_str, &endstr, 10);
/* endstr shouldnt ever equal NULL */
idx = endstr - my_str;
} else if (my_str[idx] == '$') {
*linenum = -1;
idx++;
} else if (my_str[idx] == '/' || my_str[idx] == '\\') {
int idx_start = 1;
char delimiter;
delimiter = '/';
if (my_str[idx] == '\\') {
idx_start++;
delimiter = my_str[++idx];
}
idx++;
idx += index_of_next_unescaped_regexp_delim(delimiter, my_str + idx);
if (idx == -1) {
bb_error_msg_and_die("unterminated match expression");
}
my_str[idx] = '\0';
*regex = (regex_t *) xmalloc(sizeof(regex_t));
xregcomp(*regex, my_str + idx_start, REG_NEWLINE);
idx++; /* so it points to the next character after the last '/' */
}
return idx;
}
static int parse_subst_cmd(sed_cmd_t * const sed_cmd, const char *substr)
{
int cflags = 0;
char *match;
int idx = 0;
int j;
/*
* the string that gets passed to this function should look like this:
* s/match/replace/gIp
* || | |||
* mandatory optional
*
* (all three of the '/' slashes are mandatory)
*/
idx = parse_regex_delim(substr, &match, &sed_cmd->replace);
/* 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 */
/* sed_cmd->num_backrefs = 0; *//* XXX: not needed? --apparently not */
for (j = 0; match[j]; j++) {
/* GNU/POSIX sed does not save more than nine backrefs */
if (match[j] == '\\' && match[j + 1] == '('
&& sed_cmd->num_backrefs <= 9)
sed_cmd->num_backrefs++;
}
/* process the flags */
while (substr[++idx]) {
switch (substr[idx]) {
case 'g':
sed_cmd->sub_g = 1;
break;
/* Hmm, i dont see the I option mentioned in the standard */
case 'I':
cflags |= REG_ICASE;
break;
case 'p':
sed_cmd->sub_p = 1;
break;
default:
/* any whitespace or semicolon trailing after a s/// is ok */
if (strchr(semicolon_whitespace, substr[idx]))
goto out;
/* else */
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;
}
static void replace_slash_n(char *string)
{
int i;
int remaining = strlen(string);
for (i = 0; string[i]; i++) {
if ((string[i] == '\\') && (string[i + 1] == 'n')) {
string[i] = '\n';
memmove(string + i + 1, string + i + 1, remaining - 1);
} else {
remaining--;
}
}
}
static int parse_translate_cmd(sed_cmd_t * const sed_cmd, const char *cmdstr)
{
char *match;
char *replace;
int idx;
int i;
idx = parse_regex_delim(cmdstr, &match, &replace);
replace_slash_n(match);
replace_slash_n(replace);
sed_cmd->translate = xcalloc(1, (strlen(match) + 1) * 2);
for (i = 0; (match[i] != 0) && (replace[i] != 0); i++) {
sed_cmd->translate[i * 2] = match[i];
sed_cmd->translate[(i * 2) + 1] = replace[i];
}
return (idx + 1);
}
static int parse_edit_cmd(sed_cmd_t * sed_cmd, const char *editstr)
{
int i, j;
/*
* the string that gets passed to this function should look like this:
*
* need one of these
* |
* | this backslash (immediately following the edit command) is mandatory
* | |
* [aic]\
* TEXT1\
* TEXT2\
* TEXTN
*
* as soon as we hit a TEXT line that has no trailing '\', we're done.
* this means a command like:
*
* i\
* INSERTME
*
* is a-ok.
*
*/
if ((*editstr != '\\') || ((editstr[1] != '\n') && (editstr[1] != '\r'))) {
bb_error_msg_and_die("bad format in edit expression");
}
/* store the edit line text */
sed_cmd->editline = xmalloc(strlen(&editstr[2]) + 2);
for (i = 2, j = 0;
editstr[i] != '\0' && strchr("\r\n", editstr[i]) == NULL; i++, j++) {
if ((editstr[i] == '\\') && strchr("\n\r", editstr[i + 1]) != NULL) {
sed_cmd->editline[j] = '\n';
i++;
} else
sed_cmd->editline[j] = editstr[i];
}
/* figure out if we need to add a newline */
if (sed_cmd->editline[j - 1] != '\n')
sed_cmd->editline[j++] = '\n';
/* terminate string */
sed_cmd->editline[j] = '\0';
return i;
}
static int parse_file_cmd(sed_cmd_t * sed_cmd, const char *filecmdstr)
{
int idx = 0;
int filenamelen = 0;
/*
* the string that gets passed to this function should look like this:
* '[ ]filename'
* | |
* | a filename
* |
* optional whitespace
* re: the file to be read, the GNU manual says the following: "Note that
* if filename cannot be read, it is treated as if it were an empty file,
* without any error indication." Thus, all of the following commands are
* perfectly leagal:
*
* sed -e '1r noexist'
* sed -e '1r ;'
* sed -e '1r'
*/
/* the file command may be followed by whitespace; move past it. */
while (isspace(filecmdstr[++idx])) {;
}
/* the first non-whitespace we get is a filename. the filename ends when we
* hit a normal sed command terminator or end of string */
filenamelen = strcspn(&filecmdstr[idx], semicolon_whitespace);
sed_cmd->filename = xmalloc(filenamelen + 1);
safe_strncpy(sed_cmd->filename, &filecmdstr[idx], filenamelen + 1);
return idx + filenamelen;
}
/*
* Process the commands arguments
*/
static char *parse_cmd_str(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");
cmdstr += parse_edit_cmd(sed_cmd, cmdstr);
}
/* handle file cmds: (r)ead */
else if (sed_cmd->cmd == 'r') {
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);
}
/* handle branch commands */
else if (strchr(":bt", sed_cmd->cmd)) {
int length;
cmdstr += strspn(cmdstr, " ");
length = strcspn(cmdstr, "; \n");
sed_cmd->label = strndup(cmdstr, length);
cmdstr += length;
}
/* translation command */
else if (sed_cmd->cmd == 'y') {
cmdstr += parse_translate_cmd(sed_cmd, cmdstr);
}
/* if it wasnt a single-letter command that takes no arguments
* then it must be an invalid command.
*/
else if (strchr("dghnNpPqx={}", sed_cmd->cmd) == 0) {
bb_error_msg_and_die("Unsupported command %c", sed_cmd->cmd);
}
/* give back whatever's left over */
return (cmdstr);
}
static char *add_cmd(sed_cmd_t * sed_cmd, char *cmdstr)
{
/* Skip over leading whitespace and semicolons */
cmdstr += strspn(cmdstr, semicolon_whitespace);
/* if we ate the whole thing, that means there was just trailing
* whitespace or a final / no-op semicolon. either way, get out */
if (*cmdstr == '\0') {
return (NULL);
}
/* 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++;
}
return (strpbrk(cmdstr, "\n\r"));
}
/* parse the command
* format is: [addr][,addr]cmd
* |----||-----||-|
* part1 part2 part3
*/
/* 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 == 0) {
bb_error_msg_and_die("get_address: no address found in string\n"
"\t(you probably didn't check the string you passed me)");
}
cmdstr += idx;
}
/* skip whitespace before the command */
while (isspace(*cmdstr)) {
cmdstr++;
}
/* there my be the inversion flag between part2 and part3 */
if (*cmdstr == '!') {
sed_cmd->invert = 1;
cmdstr++;
#ifdef SED_FEATURE_STRICT_CHECKING
/* According to the spec
* It is unspecified whether <blank>s can follow a '!' character,
* and conforming applications shall not follow a '!' character
* with <blank>s.
*/
if (isblank(cmdstr[idx]) {
bb_error_msg_and_die("blank follows '!'");}
#else
/* skip whitespace before the command */
while (isspace(*cmdstr)) {
cmdstr++;
}
#endif
}
/* last part (mandatory) will be a command */
if (*cmdstr == '\0')
bb_error_msg_and_die("missing command");
sed_cmd->cmd = *cmdstr;
cmdstr++;
cmdstr = parse_cmd_str(sed_cmd, cmdstr);
/* Add the command to the command array */
sed_cmd_tail->next = sed_cmd;
sed_cmd_tail = sed_cmd_tail->next;
return (cmdstr);
}
static void add_cmd_str(char *cmdstr)
{
#ifdef CONFIG_FEATURE_SED_EMBEDED_NEWLINE
char *cmdstr_ptr = cmdstr;
/* HACK: convert "\n" to match tranlated '\n' string */
while ((cmdstr_ptr = strstr(cmdstr_ptr, "\\n")) != NULL) {
cmdstr = xrealloc(cmdstr, strlen(cmdstr) + 2);
cmdstr_ptr = strstr(cmdstr, "\\n");
memmove(cmdstr_ptr + 1, cmdstr_ptr, strlen(cmdstr_ptr) + 1);
cmdstr_ptr[0] = '\\';
cmdstr_ptr += 3;
}
#endif
do {
sed_cmd_t *sed_cmd;
sed_cmd = xcalloc(1, sizeof(sed_cmd_t));
cmdstr = add_cmd(sed_cmd, cmdstr);
} while (cmdstr && strlen(cmdstr));
}
static void load_cmd_file(char *filename)
{
FILE *cmdfile;
char *line;
char *nextline;
char *e;
cmdfile = bb_xfopen(filename, "r");
while ((line = bb_get_line_from_file(cmdfile)) != NULL) {
/* if a line ends with '\' it needs the next line appended to it */
while (((e = last_char_is(line, '\n')) != NULL)
&& (e > line) && (e[-1] == '\\')
&& ((nextline = bb_get_line_from_file(cmdfile)) != NULL)) {
line = xrealloc(line, (e - line) + 1 + strlen(nextline) + 1);
strcat(line, nextline);
free(nextline);
}
/* eat trailing newline (if any) --if I don't do this, edit commands
* (aic) will print an extra newline */
chomp(line);
add_cmd_str(line);
free(line);
}
}
struct pipeline {
char *buf;
int idx;
int len;
};
#define PIPE_MAGIC 0x7f
#define PIPE_GROW 64
void pipe_putc(struct pipeline *const pipeline, char c)
{
if (pipeline->buf[pipeline->idx] == PIPE_MAGIC) {
pipeline->buf = xrealloc(pipeline->buf, pipeline->len + PIPE_GROW);
memset(pipeline->buf + pipeline->len, 0, PIPE_GROW);
pipeline->len += PIPE_GROW;
pipeline->buf[pipeline->len - 1] = PIPE_MAGIC;
}
pipeline->buf[pipeline->idx++] = (c);
}
#define pipeputc(c) pipe_putc(pipeline, c)
#if 0
{
if (pipeline[pipeline_idx] == PIPE_MAGIC) {
pipeline = xrealloc(pipeline, pipeline_len + PIPE_GROW);
memset(pipeline + pipeline_len, 0, PIPE_GROW);
pipeline_len += PIPE_GROW;
pipeline[pipeline_len - 1] = PIPE_MAGIC;
}
pipeline[pipeline_idx++] = (c);
}
#endif
static void print_subst_w_backrefs(const char *line, const char *replace,
regmatch_t * regmatch, struct pipeline *const pipeline, int matches)
{
int i;
/* 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] == '\\' && isdigit(replace[i + 1])) {
int j;
char tmpstr[2];
int backref;
++i; /* i now indexes the backref number, instead of the leading slash */
tmpstr[0] = replace[i];
tmpstr[1] = 0;
backref = atoi(tmpstr);
/* print out the text held in regmatch[backref] */
if (backref <= matches && regmatch[backref].rm_so != -1)
for (j = regmatch[backref].rm_so; j < regmatch[backref].rm_eo;
j++)
pipeputc(line[j]);
}
/* if we find a backslash escaped character, print the character */
else if (replace[i] == '\\') {
++i;
pipeputc(replace[i]);
}
/* if we find an unescaped '&' print out the whole matched text.
* fortunately, regmatch[0] contains the indicies to the whole matched
* expression (kinda seems like it was designed for just such a
* purpose...) */
else if (replace[i] == '&') {
int j;
for (j = regmatch[0].rm_so; j < regmatch[0].rm_eo; j++)
pipeputc(line[j]);
}
/* nothing special, just print this char of the replacement string to stdout */
else
pipeputc(replace[i]);
}
}
static int do_subst_command(sed_cmd_t * sed_cmd, char **line)
{
char *hackline = *line;
struct pipeline thepipe = { NULL, 0, 0 };
struct pipeline *const pipeline = &thepipe;
int altered = 0;
int result;
regmatch_t *regmatch = NULL;
regex_t *current_regex;
if (sed_cmd->sub_match == NULL) {
current_regex = previous_regex_ptr;
} else {
previous_regex_ptr = current_regex = sed_cmd->sub_match;
}
result = regexec(current_regex, hackline, 0, NULL, 0);
/* we only proceed if the substitution 'search' expression matches */
if (result == REG_NOMATCH) {
return 0;
}
/* whaddaya know, it matched. get the number of back references */
regmatch = xmalloc(sizeof(regmatch_t) * (sed_cmd->num_backrefs + 1));
/* allocate more PIPE_GROW bytes
if replaced string is larger than original */
thepipe.len = strlen(hackline) + PIPE_GROW;
thepipe.buf = xcalloc(1, thepipe.len);
/* buffer magic */
thepipe.buf[thepipe.len - 1] = PIPE_MAGIC;
/* and now, as long as we've got a line to try matching and if we can match
* the search string, we make substitutions */
while ((*hackline || !altered)
&& (regexec(current_regex, hackline, sed_cmd->num_backrefs + 1,
regmatch, 0) != REG_NOMATCH)) {
int i;
/* print everything before the match */
for (i = 0; i < regmatch[0].rm_so; i++)
pipeputc(hackline[i]);
/* then print the substitution string */
print_subst_w_backrefs(hackline, sed_cmd->replace, regmatch, pipeline,
sed_cmd->num_backrefs);
/* advance past the match */
hackline += regmatch[0].rm_eo;
/* flag that something has changed */
altered++;
/* if we're not doing this globally, get out now */
if (!sed_cmd->sub_g) {
break;
}
}
for (; *hackline; hackline++)
pipeputc(*hackline);
if (thepipe.buf[thepipe.idx] == PIPE_MAGIC)
thepipe.buf[thepipe.idx] = 0;
/* cleanup */
free(regmatch);
free(*line);
*line = thepipe.buf;
return altered;
}
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->label) && (strcmp(sed_cmd->label, label) == 0)) {
break;
}
}
/* If no match returns last command */
return (sed_cmd);
}
static void process_file(FILE * file)
{
char *pattern_space; /* Posix requires it be able to hold at least 8192 bytes */
char *hold_space = NULL; /* Posix requires it be able to hold at least 8192 bytes */
static int linenum = 0; /* GNU sed does not restart counting lines at EOF */
unsigned int still_in_range = 0;
int altered;
int force_print;
pattern_space = bb_get_chomped_line_from_file(file);
if (pattern_space == NULL) {
return;
}
/* go through every line in the file */
do {
char *next_line;
sed_cmd_t *sed_cmd;
int substituted = 0;
/* This enables whole blocks of commands to be mask'ed out if the lead address doesnt match */
int block_mask = 1;
/* Read one line in advance so we can act on the last line, the '$' address */
next_line = bb_get_chomped_line_from_file(file);
linenum++;
altered = 0;
force_print = 0;
/* for every line, go through all the commands */
for (sed_cmd = sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) {
int deleted = 0;
/*
* entry point into sedding...
*/
int matched = (
/* no range necessary */
(sed_cmd->beg_line == 0 && sed_cmd->end_line == 0
&& sed_cmd->beg_match == NULL
&& sed_cmd->end_match == NULL) ||
/* this line number is the first address we're looking for */
(sed_cmd->beg_line > 0 && (sed_cmd->beg_line == linenum)) ||
/* this line matches our first address regex */
(sed_cmd->beg_match
&& (regexec(sed_cmd->beg_match, pattern_space, 0, NULL,
0) == 0)) ||
/* we are currently within the beginning & ending address range */
still_in_range || ((sed_cmd->beg_line == -1)
&& (next_line == NULL))
);
if (sed_cmd->cmd == '{') {
block_mask = block_mask & matched;
}
// matched &= block_mask;
if (sed_cmd->invert ^ (matched & block_mask)) {
/* Update last used regex incase a blank substitute BRE is found */
if (sed_cmd->beg_match) {
previous_regex_ptr = sed_cmd->beg_match;
}
/*
* actual sedding
*/
switch (sed_cmd->cmd) {
case '=':
printf("%d\n", linenum);
break;
case 'P':{
/* Write the current pattern space upto the first newline */
char *tmp = strchr(pattern_space, '\n');
if (tmp) {
*tmp = '\0';
}
}
case 'p': /* Write the current pattern space to output */
puts(pattern_space);
break;
case 'd':
altered++;
deleted = 1;
break;
case 's':
/*
* Some special cases for 's' printing to make it compliant with
* GNU sed printing behavior (aka "The -n | s///p Matrix"):
*
* -n ONLY = never print anything regardless of any successful
* substitution
*
* s///p ONLY = always print successful substitutions, even if
* the pattern_space is going to be printed anyway (pattern_space
* will be printed twice).
*
* -n AND s///p = print ONLY a successful substitution ONE TIME;
* no other lines are printed - this is the reason why the 'p'
* flag exists in the first place.
*/
#ifdef CONFIG_FEATURE_SED_EMBEDED_NEWLINE
/* HACK: escape newlines twice so regex can match them */
{
int offset = 0;
while (strchr(pattern_space + offset, '\n') != NULL) {
char *tmp;
pattern_space =
xrealloc(pattern_space,
strlen(pattern_space) + 2);
tmp = strchr(pattern_space + offset, '\n');
memmove(tmp + 1, tmp, strlen(tmp) + 1);
tmp[0] = '\\';
tmp[1] = 'n';
offset = tmp - pattern_space + 2;
}
}
#endif
/* we print the pattern_space once, unless we were told to be quiet */
substituted = do_subst_command(sed_cmd, &pattern_space);
#ifdef CONFIG_FEATURE_SED_EMBEDED_NEWLINE
/* undo HACK: escape newlines twice so regex can match them */
{
char *tmp = pattern_space;
while ((tmp = strstr(tmp, "\\n")) != NULL) {
memmove(tmp, tmp + 1, strlen(tmp + 1) + 1);
tmp[0] = '\n';
}
}
#endif
altered |= substituted;
if (!be_quiet && altered && ((sed_cmd->next == NULL)
|| (sed_cmd->next->cmd != 's'))) {
force_print = 1;
}
/* we also print the line if we were given the 'p' flag
* (this is quite possibly the second printing) */
if ((sed_cmd->sub_p) && altered) {
puts(pattern_space);
}
break;
case 'a':
puts(pattern_space);
fputs(sed_cmd->editline, stdout);
altered++;
break;
case 'i':
fputs(sed_cmd->editline, stdout);
break;
case 'c':
/* single-address case */
if ((sed_cmd->end_match == NULL && sed_cmd->end_line == 0)
/* multi-address case */
/* - matching text */
|| (sed_cmd->end_match
&& (regexec(sed_cmd->end_match, pattern_space, 0,
NULL, 0) == 0))
/* - matching line numbers */
|| (sed_cmd->end_line > 0
&& sed_cmd->end_line == linenum)) {
fputs(sed_cmd->editline, stdout);
}
altered++;
break;
case 'r':{
FILE *outfile;
outfile = fopen(sed_cmd->filename, "r");
if (outfile) {
char *line;
while ((line =
bb_get_chomped_line_from_file(outfile)) !=
NULL) {
pattern_space =
xrealloc(pattern_space,
strlen(line) + strlen(pattern_space) + 2);
strcat(pattern_space, "\n");
strcat(pattern_space, line);
}
bb_xprint_and_close_file(outfile);
}
}
break;
case 'q': /* Branch to end of script and quit */
deleted = 1;
/* Exit the outer while loop */
free(next_line);
next_line = NULL;
break;
case 'n': /* Read next line from input */
free(pattern_space);
pattern_space = next_line;
next_line = bb_get_chomped_line_from_file(file);
linenum++;
break;
case 'N': /* Append the next line to the current line */
if (next_line) {
pattern_space =
realloc(pattern_space,
strlen(pattern_space) + strlen(next_line) + 2);
strcat(pattern_space, "\n");
strcat(pattern_space, next_line);
next_line = bb_get_chomped_line_from_file(file);
linenum++;
}
break;
case 'b':
sed_cmd = branch_to(sed_cmd->label);
break;
case 't':
if (substituted) {
sed_cmd = branch_to(sed_cmd->label);
}
break;
case 'y':{
int i;
for (i = 0; pattern_space[i] != 0; i++) {
int j;
for (j = 0; sed_cmd->translate[j]; j += 2) {
if (pattern_space[i] == sed_cmd->translate[j]) {
pattern_space[i] = sed_cmd->translate[j + 1];
}
}
}
}
break;
case 'g': /* Replace pattern space with hold space */
free(pattern_space);
pattern_space = strdup(hold_space);
break;
case 'h': /* Replace hold space with pattern space */
free(hold_space);
hold_space = strdup(pattern_space);
break;
case 'x':{
/* Swap hold and pattern space */
char *tmp = pattern_space;
pattern_space = hold_space;
hold_space = tmp;
break;
}
}
}
/*
* exit point from sedding...
*/
if (matched) {
if (
/* this is a single-address command or... */
(sed_cmd->end_line == 0 && sed_cmd->end_match == NULL)
/* If only one address */
/* we were in the middle of our address range (this
* isn't the first time through) and.. */
|| ((still_in_range == 1)
/* this line number is the last address we're looking for or... */
&& ((sed_cmd->end_line > 0
&& (sed_cmd->end_line == linenum))
/* this line matches our last address regex */
|| (sed_cmd->end_match
&& (regexec(sed_cmd->end_match, pattern_space,
0, NULL, 0) == 0))))) {
/* we're out of our address range */
still_in_range = 0;
} else {
/* didn't hit the exit? then we're still in the middle of an address range */
still_in_range = 1;
}
}
if (sed_cmd->cmd == '}') {
block_mask = 1;
}
if (deleted)
break;
}
/* we will print the line unless we were told to be quiet or if the
* line was altered (via a 'd'elete or 's'ubstitution), in which case
* the altered line was already printed */
if ((!be_quiet && !altered) || force_print) {
puts(pattern_space);
}
free(pattern_space);
pattern_space = next_line;
} while (pattern_space);
}
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(destroy_cmd_strs) == -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':{
char *str_cmd = strdup(optarg);
add_cmd_str(str_cmd);
free(str_cmd);
break;
}
case 'f':
load_cmd_file(optarg);
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 {
char *str_cmd = strdup(argv[optind]);
add_cmd_str(strdup(str_cmd));
free(str_cmd);
optind++;
}
}
/* 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 || (strcmp(argv[optind], "-") == 0)) {
process_file(stdin);
} else {
int i;
FILE *file;
for (i = optind; i < argc; i++) {
file = bb_wfopen(argv[i], "r");
if (file) {
process_file(file);
fclose(file);
} else
status = EXIT_FAILURE;
}
}
return status;
}
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