- address matching: num|/matchstr/[,num|/matchstr/|$]command
- commands: (p)rint, (d)elete, (s)ubstitue (with g & I flags)
- edit commands: (a)ppend, (i)nsert, (c)hange
+ - file commands: (r)ead
- backreferences in substitution expressions (\1, \2...\9)
(Note: Specifying an address (range) to match is *optional*; commands
/* EDIT COMMAND (a,i,c) SPEICIFIC FIELDS */
char *editline;
+
+
+ /* FILE COMMAND (r) SPEICIFIC FIELDS */
+
+ char *filename;
};
/* globals */
*/
static int index_of_next_unescaped_regexp_delim(struct sed_cmd *sed_cmd, const char *str, int idx)
{
+ int bracket = -1;
+ int escaped = 0;
+
for ( ; str[idx]; idx++) {
- if (str[idx] == sed_cmd->delimiter && str[idx-1] != '\\')
+ if (bracket != -1) {
+ if (str[idx] == ']' && !(bracket == idx - 1 ||
+ (bracket == idx - 2 && str[idx-1] == '^')))
+ bracket = -1;
+ } else if (escaped)
+ escaped = 0;
+ else if (str[idx] == '\\')
+ escaped = 1;
+ else if (str[idx] == '[')
+ bracket = idx;
+ else if (str[idx] == sed_cmd->delimiter)
return idx;
}
/*
* returns the index in the string just past where the address ends.
*/
-static int get_address(struct sed_cmd *sed_cmd, const char *str, int *line, regex_t **regex)
+static int get_address(struct sed_cmd *sed_cmd, const char *str, int *linenum, regex_t **regex)
{
char *my_str = strdup(str);
int idx = 0;
+ char olddelimiter;
+ olddelimiter = sed_cmd->delimiter;
+ sed_cmd->delimiter = '/';
if (isdigit(my_str[idx])) {
do {
idx++;
} while (isdigit(my_str[idx]));
my_str[idx] = 0;
- *line = atoi(my_str);
+ *linenum = atoi(my_str);
}
else if (my_str[idx] == '$') {
- *line = -1;
+ *linenum = -1;
idx++;
}
else if (my_str[idx] == '/') {
error_msg_and_die("unterminated match expression");
my_str[idx] = '\0';
*regex = (regex_t *)xmalloc(sizeof(regex_t));
- xregcomp(*regex, my_str+1, 0);
+ xregcomp(*regex, my_str+1, REG_NEWLINE);
idx++; /* so it points to the next character after the last '/' */
}
else {
}
free(my_str);
+ sed_cmd->delimiter = olddelimiter;
return idx;
}
-static char *strdup_substr(const char *str, int start, int end)
-{
- int size = end - start + 1;
- char *newstr = xmalloc(size);
- memcpy(newstr, str+start, size-1);
- newstr[size-1] = '\0';
- return newstr;
-}
-
static int parse_subst_cmd(struct sed_cmd *sed_cmd, const char *substr)
{
int oldidx, cflags = REG_NEWLINE;
idx = index_of_next_unescaped_regexp_delim(sed_cmd, substr, ++idx);
if (idx == -1)
error_msg_and_die("bad format in substitution expression");
- match = strdup_substr(substr, oldidx, idx);
+ match = xstrndup(substr + oldidx, idx - oldidx);
/* determine the number of back references in the match string */
/* Note: we compute this here rather than in the do_subst_command()
idx = index_of_next_unescaped_regexp_delim(sed_cmd, substr, ++idx);
if (idx == -1)
error_msg_and_die("bad format in substitution expression");
- sed_cmd->replace = strdup_substr(substr, oldidx, idx);
+ sed_cmd->replace = xstrndup(substr + oldidx, idx - oldidx);
/* process the flags */
while (substr[++idx]) {
/* now we need to go through * and: s/\\[\r\n]$/\n/g on the edit line */
while (ptr[idx]) {
- while (ptr[idx] != '\\' && (ptr[idx+1] != '\n' || ptr[idx+1] != '\r')) {
+ while (ptr[idx] != '\\' || (ptr[idx+1] != '\n' && ptr[idx+1] != '\r')) {
idx++;
if (!ptr[idx]) {
goto out;
}
out:
- ptr[idx] = '\n';
- ptr[idx+1] = 0;
-
/* this accounts for discrepancies between the modified string and the
* original string passed in to this function */
idx += slashes_eaten;
- /* this accounts for the fact that A) we started at index 3, not at index
- * 0 and B) that we added an extra '\n' at the end (if you think the next
- * line should read 'idx += 4' remember, arrays are zero-based) */
+ /* figure out if we need to add a newline */
+ if (ptr[idx-1] != '\n') {
+ ptr[idx] = '\n';
+ idx++;
+ }
- idx += 3;
+ /* terminate string */
+ ptr[idx]= 0;
+ /* adjust for opening 2 chars [aic]\ */
+ idx += 2;
return idx;
}
+
+static int parse_file_cmd(struct sed_cmd *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], "; \n\r\t\v\0");
+ sed_cmd->filename = xmalloc(filenamelen + 1);
+ safe_strncpy(sed_cmd->filename, &filecmdstr[idx], filenamelen + 1);
+
+ return idx + filenamelen;
+}
+
+
static char *parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr)
{
int idx = 0;
* part1 part2 part3
*/
-
/* first part (if present) is an address: either a number or a /regex/ */
if (isdigit(cmdstr[idx]) || cmdstr[idx] == '/')
idx = get_address(sed_cmd, cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match);
/* last part (mandatory) will be a command */
if (cmdstr[idx] == '\0')
error_msg_and_die("missing command");
- if (!strchr("pdsaic", cmdstr[idx])) /* <-- XXX add new commands here */
- error_msg_and_die("invalid command");
sed_cmd->cmd = cmdstr[idx];
- /* special-case handling for (s)ubstitution */
- if (sed_cmd->cmd == 's') {
+ /* if it was a single-letter command that takes no arguments (such as 'p'
+ * or 'd') all we need to do is increment the index past that command */
+ if (strchr("pd", cmdstr[idx])) {
+ idx++;
+ }
+ /* handle (s)ubstitution command */
+ else if (sed_cmd->cmd == 's') {
idx += parse_subst_cmd(sed_cmd, &cmdstr[idx]);
}
- /* special-case handling for (a)ppend, (i)nsert, and (c)hange */
- else if (strchr("aic", cmdstr[idx])) {
- if (sed_cmd->end_line || sed_cmd->end_match)
+ /* 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')
error_msg_and_die("only a beginning address can be specified for edit commands");
idx += parse_edit_cmd(sed_cmd, &cmdstr[idx]);
}
- /* if it was a single-letter command (such as 'p' or 'd') we need to
- * increment the index past that command */
- else
- idx++;
+ /* handle file cmds: (r)ead */
+ else if (sed_cmd->cmd == 'r') {
+ if (sed_cmd->end_line || sed_cmd->end_match)
+ error_msg_and_die("Command only uses one address");
+ idx += parse_file_cmd(sed_cmd, &cmdstr[idx]);
+ }
+ else {
+ error_msg_and_die("invalid command");
+ }
/* give back whatever's left over */
return (char *)&cmdstr[idx];
}
}
-static void print_subst_w_backrefs(const char *line, const char *replace, regmatch_t *regmatch)
+#define PIPE_MAGIC 0x7f
+#define PIPE_GROW 64
+#define pipeputc(c) \
+{ 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); }
+
+static void print_subst_w_backrefs(const char *line, const char *replace,
+ regmatch_t *regmatch, char **pipeline_p, int *pipeline_idx_p,
+ int *pipeline_len_p, int matches)
{
+ char *pipeline = *pipeline_p;
+ int pipeline_idx = *pipeline_idx_p;
+ int pipeline_len = *pipeline_len_p;
int i;
/* go through the replacement string */
tmpstr[1] = 0;
backref = atoi(tmpstr);
/* print out the text held in regmatch[backref] */
- for (j = regmatch[backref].rm_so; j < regmatch[backref].rm_eo; j++)
- fputc(line[j], stdout);
+ 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;
- fputc(replace[i], stdout);
+ pipeputc(replace[i]);
}
/* if we find an unescaped '&' print out the whole matched text.
else if (replace[i] == '&' && replace[i-1] != '\\') {
int j;
for (j = regmatch[0].rm_so; j < regmatch[0].rm_eo; j++)
- fputc(line[j], stdout);
+ pipeputc(line[j]);
}
/* nothing special, just print this char of the replacement string to stdout */
else
- fputc(replace[i], stdout);
+ pipeputc(replace[i]);
}
+ *pipeline_p = pipeline;
+ *pipeline_idx_p = pipeline_idx;
+ *pipeline_len_p = pipeline_len;
}
-static int do_subst_command(const struct sed_cmd *sed_cmd, const char *line)
+static int do_subst_command(const struct sed_cmd *sed_cmd, char **line)
{
- char *hackline = (char *)line;
+ char *hackline = *line;
+ char *pipeline = 0;
+ int pipeline_idx = 0;
+ int pipeline_len = 0;
int altered = 0;
regmatch_t *regmatch = NULL;
/* we only proceed if the substitution 'search' expression matches */
- if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == REG_NOMATCH)
+ if (regexec(sed_cmd->sub_match, hackline, 0, NULL, 0) == 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 */
+ pipeline_len = strlen(hackline)+PIPE_GROW;
+ pipeline = xmalloc(pipeline_len);
+ memset(pipeline, 0, pipeline_len);
+ /* buffer magic */
+ pipeline[pipeline_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 && (regexec(sed_cmd->sub_match, hackline,
/* print everything before the match */
for (i = 0; i < regmatch[0].rm_so; i++)
- fputc(hackline[i], stdout);
+ pipeputc(hackline[i]);
/* then print the substitution string */
- print_subst_w_backrefs(hackline, sed_cmd->replace, regmatch);
+ print_subst_w_backrefs(hackline, sed_cmd->replace, regmatch,
+ &pipeline, &pipeline_idx, &pipeline_len,
+ sed_cmd->num_backrefs);
/* advance past the match */
hackline += regmatch[0].rm_eo;
break;
}
- /* if there's anything left of the line, print it */
- if (*hackline)
- fputs(hackline, stdout);
+ for (; *hackline; hackline++) pipeputc(*hackline);
+ if (pipeline[pipeline_idx] == PIPE_MAGIC) pipeline[pipeline_idx] = 0;
/* cleanup */
free(regmatch);
+ free(*line);
+ *line = pipeline;
return altered;
}
-static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line)
-{
- int altered = 0;
-
- switch (sed_cmd->cmd) {
-
- case 'p':
- fputs(line, stdout);
- break;
-
- case 'd':
- altered++;
- 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 line is going to be printed anyway (line 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.
- */
-
- /* if the user specified that they didn't want anything printed (i.e. a -n
- * flag and no 'p' flag after the s///), then there's really no point doing
- * anything here. */
- if (be_quiet && !sed_cmd->sub_p)
- break;
-
- /* we print the line once, unless we were told to be quiet */
- if (!be_quiet)
- altered = do_subst_command(sed_cmd, line);
-
- /* 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 = do_subst_command(sed_cmd, line);
-
- break;
-
- case 'a':
- fputs(line, stdout);
- fputs(sed_cmd->editline, stdout);
- altered++;
- break;
-
- case 'i':
- fputs(sed_cmd->editline, stdout);
- break;
-
- case 'c':
- fputs(sed_cmd->editline, stdout);
- altered++;
- break;
- }
-
- return altered;
-}
static void process_file(FILE *file)
{
char *line = NULL;
static int linenum = 0; /* GNU sed does not restart counting lines at EOF */
unsigned int still_in_range = 0;
- int line_altered;
+ int altered;
int i;
/* go through every line in the file */
while ((line = get_line_from_file(file)) != NULL) {
+ chomp(line);
linenum++;
- line_altered = 0;
+ altered = 0;
/* for every line, go through all the commands */
for (i = 0; i < ncmds; i++) {
- /* are we acting on a range of matched lines? */
- if (sed_cmds[i].beg_match && sed_cmds[i].end_match) {
- if (still_in_range || regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0) {
- line_altered += do_sed_command(&sed_cmds[i], line);
- still_in_range = 1;
- if (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0)
- still_in_range = 0;
- }
- }
- /* are we trying to match a single line? */
- else if (sed_cmds[i].beg_match) {
- if (regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0)
- line_altered += do_sed_command(&sed_cmds[i], line);
- }
+ /*
+ * entry point into sedding...
+ */
+ if (
+ /* no range necessary */
+ (sed_cmds[i].beg_line == 0 && sed_cmds[i].end_line == 0 &&
+ sed_cmds[i].beg_match == NULL &&
+ sed_cmds[i].end_match == NULL) ||
+ /* this line number is the first address we're looking for */
+ (sed_cmds[i].beg_line && (sed_cmds[i].beg_line == linenum)) ||
+ /* this line matches our first address regex */
+ (sed_cmds[i].beg_match && (regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0)) ||
+ /* we are currently within the beginning & ending address range */
+ still_in_range
+ ) {
+
+ /*
+ * actual sedding
+ */
+ switch (sed_cmds[i].cmd) {
+
+ case 'p':
+ puts(line);
+ break;
+
+ case 'd':
+ altered++;
+ 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 line is going to be printed anyway (line 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.
+ */
+
+ /* if the user specified that they didn't want anything printed (i.e., a -n
+ * flag and no 'p' flag after the s///), then there's really no point doing
+ * anything here. */
+ if (be_quiet && !sed_cmds[i].sub_p)
+ break;
+
+ /* we print the line once, unless we were told to be quiet */
+ if (!be_quiet)
+ altered |= do_subst_command(&sed_cmds[i], &line);
+
+ /* we also print the line if we were given the 'p' flag
+ * (this is quite possibly the second printing) */
+ if (sed_cmds[i].sub_p)
+ altered |= do_subst_command(&sed_cmds[i], &line);
+ if (altered && (i+1 >= ncmds || sed_cmds[i+1].cmd != 's'))
+ puts(line);
+
+ break;
+
+ case 'a':
+ puts(line);
+ fputs(sed_cmds[i].editline, stdout);
+ altered++;
+ break;
+
+ case 'i':
+ fputs(sed_cmds[i].editline, stdout);
+ break;
+
+ case 'c':
+ /* single-address case */
+ if (sed_cmds[i].end_match == NULL && sed_cmds[i].end_line == 0) {
+ fputs(sed_cmds[i].editline, stdout);
+ }
+ /* multi-address case */
+ else {
+ /* matching text */
+ if (sed_cmds[i].end_match && (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0))
+ fputs(sed_cmds[i].editline, stdout);
+ /* matching line numbers */
+ if (sed_cmds[i].end_line > 0 && sed_cmds[i].end_line == linenum)
+ fputs(sed_cmds[i].editline, stdout);
+ }
+ altered++;
+
+ break;
+
+ case 'r': {
+ FILE *outfile;
+ puts(line);
+ outfile = fopen(sed_cmds[i].filename, "r");
+ if (outfile)
+ print_file(outfile);
+ /* else if we couldn't open the output file,
+ * no biggie, just don't print anything */
+ altered++;
+ }
+ break;
+ }
- /* are we acting on a range of line numbers? */
- else if (sed_cmds[i].beg_line > 0 && sed_cmds[i].end_line != 0) {
- if (linenum >= sed_cmds[i].beg_line &&
- (sed_cmds[i].end_line == -1 || linenum <= sed_cmds[i].end_line))
- line_altered += do_sed_command(&sed_cmds[i], line);
- }
+ /*
+ * exit point from sedding...
+ */
+ if (
+ /* this is a single-address command or... */
+ (sed_cmds[i].end_line == 0 && sed_cmds[i].end_match == NULL) || (
+ /* 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_cmds[i].end_line && (sed_cmds[i].end_line == linenum)) ||
+ /* this line matches our last address regex */
+ (sed_cmds[i].end_match && (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0))
+ )
+ )
+ ) {
+ /* we're out of our address range */
+ still_in_range = 0;
+ }
- /* are we acting on a specified line number */
- else if (sed_cmds[i].beg_line > 0) {
- if (linenum == sed_cmds[i].beg_line)
- line_altered += do_sed_command(&sed_cmds[i], line);
+ /* didn't hit the exit? then we're still in the middle of an address range */
+ else {
+ still_in_range = 1;
+ }
}
-
- /* not acting on matches or line numbers. act on every line */
- else
- line_altered += do_sed_command(&sed_cmds[i], line);
-
}
/* 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 && !line_altered)
- fputs(line, stdout);
+ if (!be_quiet && !altered)
+ puts(line);
free(line);
}