diff options
| -rw-r--r-- | toys/pending/sed.c | 189 |
1 files changed, 85 insertions, 104 deletions
diff --git a/toys/pending/sed.c b/toys/pending/sed.c index 22e07c07..83119bf8 100644 --- a/toys/pending/sed.c +++ b/toys/pending/sed.c @@ -1,137 +1,118 @@ -/* sed.c - Stream editor. +/* sed.c - stream editor * - * Copyright 2012 Rob Landley <rob@landley.net> + * Copyright 2014 Rob Landley <rob@landley.net> * - * See http://opengroup.org/onlinepubs/9699919799/utilities/sed.c + * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/sed.html + * + * todo "-e blah -f blah -e blah" what order? + * What happens when first address matched, then EOF? How about ",42" or "1," + * Does $ match last line of file or last line of input + * If file doesn't end with newline + * command preceded by whitespace. whitespace before rw or s///w file + * space before address + * numerical addresses that cross, select one line + * test backslash escapes in regex; share code with printf? -USE_SED(NEWTOY(sed, "irne*f*", TOYFLAG_BIN)) +USE_SED(NEWTOY(sed, "e*f*inr", TOYFLAG_USR|TOYFLAG_BIN)) config SED bool "sed" default n help - usage: sed [-irn] {command | [-e command]...} [FILE...] + usage: sed [-inr] [-e SCRIPT]...|SCRIPT [-f SCRIPT_FILE]... [FILE...] + + Stream editor. Apply one or more editing SCRIPTs to each line of each line + of input (from FILE or stdin) producing output (by default to stdout). + + -e add SCRIPT to list + -f add contents of SCRIPT_FILE to list + -i Edit each file in place. + -n No default output. (Use the p command to output matched lines.) + -r Use extended regular expression syntax. + + A SCRIPT is a series of one or more COMMANDs separated by newlines or + semicolons. All -e SCRIPTs are concatenated together as if separated + by newlines, followed by all lines from -f SCRIPT_FILEs, in order. + If no -e or -f SCRIPTs are specified, the first argument is the SCRIPT. + + Each COMMAND may be preceded by an address which limits the command to + run only on the specified lines: + + [ADDRESS[,ADDRESS]]COMMAND + + The ADDRESS may be a decimal line number (starting at 1), a /regular + expression/ within a pair of forward slashes, or the character "$" which + matches the last line of input. A single address matches one line, a pair + of comma separated addresses match everything from the first address to + the second address (inclusive). If both addresses are regular expressions, + more than one range of lines in each file can match. + + REGULAR EXPRESSIONS in sed are started and ended by the same character + (traditionally / but anything except a backslash or a newline works). + Backslashes may be used to escape the delimiter if it occurs in the + regex, and for the usual printf escapes (\abcefnrtv and octal, hex, + and unicode). An empty regex repeats the previous one. ADDRESS regexes + (above) require the first delimeter to be escaped with a backslash when + it isn't a forward slash (to distinguish it from the COMMANDs below). + + Each COMMAND starts with a single character, which may be followed by + additional data depending on the COMMAND: + + rwbrstwy:{ + + s search and replace - Stream EDitor, transforms text by appling script of command to each line - of input. + The search and replace syntax - -e Add expression to the command script (if no -e, use first argument) - -i Modify file in place - -n No default output (p commands only) - -r Use extended regular expression syntex + Deviations from posix: we allow extended regular expressions with -r, + editing in place with -i, printf escapes in text, semicolons after. */ #define FOR_sed #include "toys.h" GLOBALS( - struct arg_list *files; - struct arg_list *scripts; + struct arg_list *f; + struct arg_list *e; - void *commands; + void *pattern; ) -// Digested version of what sed commands can actually tell use to do. - - -struct sed_command { - // double_list compatibility (easier to create in-order) - struct sed_command *next, *prev; - - // data string for (saicytb) - char c, *data; - // Regexes for s/match/data/ and /begin/,/end/command - regex_t *rmatch, *rbegin, *rend; - // For numeric ranges ala 10,20command - long lstart, lstop; - // Which match to replace, 0 for all. s and w commands can write to a file - int which, outfd; -}; - -// Space. Space. Gotta get past space. Spaaaaaaaace! (But not newline.) -static void spaceorb(char **s) +static void do_line(char **pline, long len) { - while (**s == ' ' || **s == '\t') ++*s; + printf("len=%ld line=%s\n", len, *pline); } -// Parse sed commands - -static void parse_scripts(void) +static void do_lines(int fd, char *name, void (*call)(char **pline, long len)) { - struct arg_list *script; - int which = 0, i; - - // Loop through list of scripts collated from command line and/or files - - for (script = TT.scripts; script; script = script->next) { - char *str = script->arg; - struct sed_command *cmd; - - // we can get multiple commands from a string (semicolons and such) - - which++; - for (i=1;;) { - if (!*str) break; - - cmd = xzalloc(sizeof(struct sed_command)); - - // Identify prefix - for (;;) { - spaceorb(&str); - if (*str == '^') { - if (cmd->lstart) goto parse_fail; - cmd->lstart = -1; - str++; - continue; - } else if (*str == '$') { - cmd->lstop = LONG_MAX; - str++; - break; - } else if (isdigit(*str)) { - long ll = strtol(str, &str, 10); - - if (ll<0) goto parse_fail; - if (cmd->lstart) { - cmd->lstop = ll; - break; - } else cmd->lstart = ll; - } else if (*str == '/' || *str == '\\') { - // set begin/end - printf("regex\n"); - exit(1); - } else if (!cmd->lstart && !cmd->rbegin) break; - else goto parse_fail; // , with no range after it - - spaceorb(&str); - if (*str != ',') break; - str++; - } - i = stridx("{bcdDgGhHlnNpPstwxyrqia= \t#:}", *str); - if (i == -1) goto parse_fail; - - dlist_add_nomalloc((struct double_list **)&TT.commands, - (struct double_list *)cmd); - exit(1); - } - } + FILE *fp = fdopen(fd, "r"); - return; + for (;;) { + char *line = 0; + ssize_t len; -parse_fail: - error_exit("bad expression %d@%d: %s", which, i, script->arg+i); + len = getline(&line, (void *)&len, fp); + do_line(&line, len); + free(line); + if (len < 1) break; + } +} + +static void do_sed(int fd, char *name) +{ + do_lines(fd, name, do_line); } void sed_main(void) { - char **files=toys.optargs; + char **args = toys.optargs; - // If no -e, use first argument - if (!TT.scripts) { - if (!*files) error_exit("Need script"); - (TT.scripts = xzalloc(sizeof(struct arg_list)))->arg = *(files++); + // Need a pattern + if (!TT.e) { + if (!*toys.optargs) error_exit("no pattern"); + (TT.e = xzalloc(sizeof(struct arg_list)))->arg = *(args++); } - parse_scripts(); - - while (*files) dprintf(2,"file=%s\n", *(files++)); + // Inflict pattern upon input files + loopfiles(args, do_sed); } |