#pragma prototyped

#include "defs.h"

#include "edit.h"

#if ! SHOPT_HISTEXPAND

NoN(hexpand)

#else

static char *modifiers = "htrepqxs&";

static int mod_flags[] = { 0, 0, 0, 0, HIST_PRINT, HIST_QUOTE, HIST_QUOTE|HIST_QUOTE_BR, 0, 0 };

#define DONE() {flag |= HIST_ERROR; cp = 0; stakseek(0); goto done;}

struct subst

{

char *str[2]; /* [0] is "old", [1] is "new" string */

};

static char *parse_subst(const char *s, struct subst *sb)

{

char *cp,del;

int off,n = 0;

/* build the strings on the stack, mainly for '&' substition in "new" */

off = staktell();

/* init "new" with empty string */

if(sb->str[1])

free(sb->str[1]);

sb->str[1] = strdup("");

/* get delimiter */

del = *s;

cp = (char*) s + 1;

while(n < 2)

{

if(*cp == del || *cp == '\n' || *cp == '\0')

{

/* delimiter or EOL */

if(staktell() != off)

{

/* dupe string on stack and rewind stack */

stakputc('\0');

if(sb->str[n])

free(sb->str[n]);

sb->str[n] = strdup(stakptr(off));

stakseek(off);

}

n++;

/* if not delimiter, we've reached EOL. Get outta here. */

if(*cp != del)

break;

}

else if(*cp == '\\')

{

if(*(cp+1) == del) /* quote delimiter */

{

stakputc(del);

cp++;

}

else if(*(cp+1) == '&' && n == 1)

{ /* quote '&' only in "new" */

stakputc('&');

cp++;

}

else

stakputc('\\');

}

else if(*cp == '&' && n == 1 && sb->str[0])

/* substitute '&' with "old" in "new" */

stakputs(sb->str[0]);

else

stakputc(*cp);

cp++;

}

/* rewind stack */

stakseek(off);

return cp;

}

int hist_expand(const char *ln, char **xp)

{

int off, /* stack offset */

q, /* quotation flags */

p, /* flag */

c, /* current char */

flag=0; /* HIST_* flags */

Sfoff_t n, /* history line number, counter, etc. */

i, /* counter */

w[2]; /* word range */

char *sp, /* stack pointer */

*cp, /* current char in ln */

*str, /* search string */

*evp, /* event/word designator string, for error msgs */

*cc=0, /* copy of current line up to cp; temp ptr */

hc[3], /* default histchars */

*qc="\'\"`"; /* quote characters */

Sfio_t *ref=0, /* line referenced by event designator */

*tmp=0, /* temporary line buffer */

*tmp2=0;/* temporary line buffer */

Histloc_t hl; /* history location */

static Namval_t *np = 0; /* histchars variable */

static struct subst sb = {0,0}; /* substition strings */

static Sfio_t *wm=0; /* word match from !?string? event designator */

if(!wm)

wm = sfopen(NULL, NULL, "swr");

hc[0] = '!';

hc[1] = '^';

hc[2] = 0;

if((np = nv_open("histchars",sh.var_tree,0)) && (cp = nv_getval(np)))

{

if(cp[0])

{

hc[0] = cp[0];

if(cp[1])

{

hc[1] = cp[1];

if(cp[2])

hc[2] = cp[2];

}

}

}

/* save shell stack */

if(off = staktell())

sp = stakfreeze(0);

cp = (char*)ln;

while(cp && *cp)

{

/* read until event/quick substitution/comment designator */

if((*cp != hc[0] && *cp != hc[1] && *cp != hc[2])

|| (*cp == hc[1] && cp != ln))

{

if(*cp == '\\') /* skip escaped designators */

stakputc(*cp++);

else if(*cp == '\'') /* skip quoted designators */

{

do

stakputc(*cp);

while(*++cp && *cp != '\'');

}

stakputc(*cp++);

continue;

}

if(hc[2] && *cp == hc[2]) /* history comment designator, skip rest of line */

{

stakputc(*cp++);

stakputs(cp);

DONE();

}

n = -1;

str = 0;

flag &= HIST_EVENT; /* save event flag for returning later */

evp = cp;

ref = 0;

if(*cp == hc[1]) /* shortcut substitution */

{

flag |= HIST_QUICKSUBST;

goto getline;

}

if(*cp == hc[0] && *(cp+1) == hc[0]) /* refer to line -1 */

{

cp += 2;

goto getline;

}

switch(c = *++cp) {

case ' ':

case '\t':

case '\n':

case '\0':

case '=':

case '(':

stakputc(hc[0]);

continue;

case '#': /* the line up to current position */

flag |= HIST_HASH;

cp++;

n = staktell(); /* terminate string and dup */

stakputc('\0');

cc = strdup(stakptr(0));

stakseek(n); /* remove null byte again */

ref = sfopen(ref, cc, "s"); /* open as file */

n = 0; /* skip history file referencing */

break;

case '-': /* back reference by number */

if(!isdigit(*(cp+1)))

goto string_event;

cp++;

case '0': /* reference by number */

case '1':

case '2':

case '3':

case '4':

case '5':

case '6':

case '7':

case '8':

case '9':

n = 0;

while(isdigit(*cp))

n = n * 10 + (*cp++) - '0';

if(c == '-')

n = -n;

break;

case '$':

n = -1;

case ':':

break;

case '?':

cp++;

flag |= HIST_QUESTION;

string_event:

default:

/* read until end of string or word designator/modifier */

str = cp;

while(*cp)

{

cp++;

if((!(flag&HIST_QUESTION) &&

(*cp == ':' || isspace(*cp)

|| *cp == '^' || *cp == '$'

|| *cp == '*' || *cp == '-'

|| *cp == '%')

)

|| ((flag&HIST_QUESTION) && (*cp == '?' || *cp == '\n')))

{

c = *cp;

*cp = '\0';

}

}

break;

}

getline:

flag |= HIST_EVENT;

if(str) /* !string or !?string? event designator */

{

/* search history for string */

hl = hist_find(sh.hist_ptr, str,

sh.hist_ptr->histind,

flag&HIST_QUESTION, -1);

if((n = hl.hist_command) == -1)

n = 0; /* not found */

}

if(n)

{

if(n < 0) /* determine index for backref */

n = sh.hist_ptr->histind + n;

/* search and use history file if found */

if(n > 0 && hist_seek(sh.hist_ptr, n) != -1)

ref = sh.hist_ptr->histfp;

}

if(!ref)

{

/* string not found or command # out of range */

c = *cp;

*cp = '\0';

errormsg(SH_DICT, ERROR_ERROR, "%s: event not found", evp);

*cp = c;

DONE();

}

if(str) /* string search: restore orig. line */

{

if(flag&HIST_QUESTION)

*cp++ = c; /* skip second question mark */

else

*cp = c;

}

/* colon introduces either word designators or modifiers */

if(*(evp = cp) == ':')

cp++;

w[0] = 0; /* -1 means last word, -2 means match from !?string? */

w[1] = -1; /* -1 means last word, -2 means suppress last word */

if(flag & HIST_QUICKSUBST) /* shortcut substitution */

goto getsel;

n = 0;

while(n < 2)

{

switch(c = *cp++) {

case '^': /* first word */

if(n == 0)

{

w[0] = w[1] = 1;

goto skip;

}

else

goto skip2;

case '$': /* last word */

w[n] = -1;

goto skip;

case '%': /* match from !?string? event designator */

if(n == 0)

{

if(!str)

{

w[0] = 0;

w[1] = -1;

ref = wm;

}

else

{

w[0] = -2;

w[1] = sftell(ref) + hl.hist_char;

}

sfseek(wm, 0, SEEK_SET);

goto skip;

}

default:

skip2:

cp--;

n = 2;

break;

case '*': /* until last word */

if(n == 0)

w[0] = 1;

w[1] = -1;

skip:

flag |= HIST_WORDDSGN;

n = 2;

break;

case '-': /* until last word or specified index */

w[1] = -2;

flag |= HIST_WORDDSGN;

n = 1;

break;

case '0':

case '1':

case '2':

case '3':

case '4':

case '5':

case '6':

case '7':

case '8':

case '9': /* specify index */

if((*evp == ':') || w[1] == -2)

{

w[n] = c - '0';

while(isdigit(c=*cp++))

w[n] = w[n] * 10 + c - '0';

flag |= HIST_WORDDSGN;

if(n == 0)

w[1] = w[0];

n++;

}

else

n = 2;

cp--;

break;

}

}

if(w[0] != -2 && w[1] > 0 && w[0] > w[1])

{

c = *cp;

*cp = '\0';

errormsg(SH_DICT, ERROR_ERROR, "%s: bad word specifier", evp);

*cp = c;

DONE();

}

/* no valid word designator after colon, rewind */

if(!(flag & HIST_WORDDSGN) && (*evp == ':'))

cp = evp;

getsel:

/* open temp buffer, let sfio do the (re)allocation */

tmp = sfopen(NULL, NULL, "swr");

/* push selected words into buffer, squash

n = i = q = 0;

while((c = sfgetc(ref)) > 0)

{

if(isspace(c))

{

flag |= (c == '\n' ? HIST_NEWLINE : 0);

continue;

}

if(n >= w[0] && ((w[0] != -2) ? (w[1] < 0 || n <= w[1]) : 1))

{

if(w[0] < 0)

sfseek(tmp, 0, SEEK_SET);

else

i = sftell(tmp);

if(i > 0)

sfputc(tmp, flag & HIST_NEWLINE ? '\n' : ' ');

flag &= ~HIST_NEWLINE;

p = 1;

}

else

p = 0;

do

{

cc = strchr(qc, c);

q ^= cc ? 1<<(int)(cc - qc) : 0;

if(p)

sfputc(tmp, c);

}

while((c = sfgetc(ref)) > 0 && (!isspace(c) || q));

if(w[0] == -2 && sftell(ref) > w[1])

break;

flag |= (c == '\n' ? HIST_NEWLINE : 0);

n++;

}

if(w[0] != -2 && w[1] >= 0 && w[1] >= n)

{

c = *cp;

*cp = '\0';

errormsg(SH_DICT, ERROR_ERROR, "%s: bad word specifier", evp);

*cp = c;

DONE();

}

else if(w[1] == -2) /* skip last word */

sfseek(tmp, i, SEEK_SET);

/* remove trailing newline */

if(sftell(tmp))

{

sfseek(tmp, -1, SEEK_CUR);

if(sfgetc(tmp) == '\n')

sfungetc(tmp, '\n');

}

sfputc(tmp, '\0');

if(str)

{

if(wm)

sfclose(wm);

wm = tmp;

}

if(cc && (flag&HIST_HASH))

{

/* close !# temp file */

sfclose(ref);

flag &= ~HIST_HASH;

free(cc);

cc = 0;

}

evp = cp;

/* selected line/words are now in buffer, now go for the modifiers */

while(*cp == ':' || (flag & HIST_QUICKSUBST))

{

if(flag & HIST_QUICKSUBST)

{

flag &= ~HIST_QUICKSUBST;

c = 's';

cp--;

}

else

c = *++cp;

sfseek(tmp, 0, SEEK_SET);

tmp2 = sfopen(tmp2, NULL, "swr");

if(c == 'g') /* global substitution */

{

flag |= HIST_GLOBALSUBST;

c = *++cp;

}

if(cc = strchr(modifiers, c))

flag |= mod_flags[cc - modifiers];

else

{

errormsg(SH_DICT, ERROR_ERROR, "%c: unrecognized history modifier", c);

DONE();

}

if(c == 'h' || c == 'r') /* head or base */

{

n = -1;

while((c = sfgetc(tmp)) > 0)

{ /* remember position of / or . */

if((c == '/' && *cp == 'h') || (c == '.' && *cp == 'r'))

n = sftell(tmp2);

sfputc(tmp2, c);

}

if(n > 0)

{ /* rewind to last / or . */

sfseek(tmp2, n, SEEK_SET);

/* end string there */

sfputc(tmp2, '\0');

}

}

else if(c == 't' || c == 'e') /* tail or suffix */

{

n = 0;

while((c = sfgetc(tmp)) > 0)

{ /* remember position of / or . */

if((c == '/' && *cp == 't') || (c == '.' && *cp == 'e'))

n = sftell(tmp);

}

/* rewind to last / or . */

sfseek(tmp, n, SEEK_SET);

/* copy from there on */

while((c = sfgetc(tmp)) > 0)

sfputc(tmp2, c);

}

else if(c == 's' || c == '&')

{

cp++;

if(c == 's')

{

/* preset old with match from !?string? */

if(!sb.str[0] && wm)

sb.str[0] = strdup(sfsetbuf(wm, (Void_t*)1, 0));

cp = parse_subst(cp, &sb);

}

if(!sb.str[0] || !sb.str[1])

{

c = *cp;

*cp = '\0';

errormsg(SH_DICT, ERROR_ERROR,

"%s%s: no previous substitution",

(flag & HIST_QUICKSUBST) ? ":s" : "",

evp);

*cp = c;

DONE();

}

/* need pointer for strstr() */

str = sfsetbuf(tmp, (Void_t*)1, 0);

flag |= HIST_SUBSTITUTE;

while(flag & HIST_SUBSTITUTE)

{

/* find string */

if(cc = strstr(str, sb.str[0]))

{ /* replace it */

c = *cc;

*cc = '\0';

sfputr(tmp2, str, -1);

sfputr(tmp2, sb.str[1], -1);

*cc = c;

str = cc + strlen(sb.str[0]);

}

else if(!sftell(tmp2))

{ /* not successfull */

c = *cp;

*cp = '\0';

errormsg(SH_DICT, ERROR_ERROR,

"%s%s: substitution failed",

(flag & HIST_QUICKSUBST) ? ":s" : "",

evp);

*cp = c;

DONE();

}

/* loop if g modifier specified */

if(!cc || !(flag & HIST_GLOBALSUBST))

flag &= ~HIST_SUBSTITUTE;

}

/* output rest of line */

sfputr(tmp2, str, -1);

if(*cp)

cp--;

}

if(sftell(tmp2))

{ /* if any substitions done, swap buffers */

if(wm != tmp)

sfclose(tmp);

tmp = tmp2;

tmp2 = 0;

}

cc = 0;

if(*cp)

cp++;

}

/* flush temporary buffer to stack */

if(tmp)

{

sfseek(tmp, 0, SEEK_SET);

if(flag & HIST_QUOTE)

stakputc('\'');

while((c = sfgetc(tmp)) > 0)

{

if(isspace(c))

{

flag = flag & ~HIST_NEWLINE;

/* squash white space to either a

do

flag |= (c == '\n' ? HIST_NEWLINE : 0);

while((c = sfgetc(tmp)) > 0 && isspace(c));

sfungetc(tmp, c);

c = (flag & HIST_NEWLINE) ? '\n' : ' ';

if(flag & HIST_QUOTE_BR)

{

stakputc('\'');

stakputc(c);

stakputc('\'');

}

else

stakputc(c);

}

else if((c == '\'') && (flag & HIST_QUOTE))

{

stakputc('\'');

stakputc('\\');

stakputc(c);

stakputc('\'');

}

else

stakputc(c);

}

if(flag & HIST_QUOTE)

stakputc('\'');

}

}

stakputc('\0');

done:

if(cc && (flag&HIST_HASH))

{

/* close !# temp file */

sfclose(ref);

free(cc);

cc = 0;

}

/* error? */

if(staktell() && !(flag & HIST_ERROR))

*xp = strdup(stakfreeze(1));

/* restore shell stack */

if(off)

stakset(sp,off);

else

stakseek(0);

/* drop temporary files */

if(tmp && tmp != wm)

sfclose(tmp);

if(tmp2)

sfclose(tmp2);

return (flag & HIST_ERROR ? HIST_ERROR : flag & HIST_FLAG_RETURN_MASK);

}

#endif