From cb064374c86259f74899162b28c4896e898401e3 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Thu, 3 Sep 2020 05:42:59 -0500 Subject: Implement brace sequence expressions ala {a..z} and {1..37..2} --- toys/pending/sh.c | 126 +++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 86 insertions(+), 40 deletions(-) (limited to 'toys/pending') diff --git a/toys/pending/sh.c b/toys/pending/sh.c index e95f98ad..797b96a3 100644 --- a/toys/pending/sh.c +++ b/toys/pending/sh.c @@ -1293,36 +1293,76 @@ fail: return !!arg; } +struct sh_brace { + struct sh_brace *next, *prev, *stack; + int active, cnt, idx, commas[]; +}; + +static int brace_end(struct sh_brace *bb) +{ + return bb->commas[(bb->cnt<0 ? 0 : bb->cnt)+1]; +} + // expand braces (ala {a,b,c}) and call expand_arg_nobrace() each permutation static int expand_arg(struct sh_arg *arg, char *old, unsigned flags, struct arg_list **delete) { - struct brace { - struct brace *next, *prev, *stack; - int active, cnt, idx, dots[2], commas[]; - } *bb = 0, *blist = 0, *bstk, *bnext; - int i, j; + struct sh_brace *bb = 0, *blist = 0, *bstk, *bnext; + int i, j, k, x; char *s, *ss; // collect brace spans if ((TT.options&OPT_BRACE) && !(flags&NO_BRACE)) for (i = 0; ; i++) { + // skip quoted/escaped text while ((s = parse_word(old+i, 1, 0)) != old+i) i += s-(old+i); + // stop at end of string if we haven't got any more open braces if (!bb && !old[i]) break; + // end a brace? if (bb && (!old[i] || old[i] == '}')) { bb->active = bb->commas[bb->cnt+1] = i; - for (bnext = bb; bb && bb->active; bb = (bb==blist)?0:bb->prev); - if (!old[i] || !bnext->cnt) // discard commaless brace from start/middle + // pop brace from bb into bnext + for (bnext = bb; bb && bb->active; bb = (bb==blist) ? 0 : bb->prev); + // Is this a .. span? + j = 1+*bnext->commas; + if (old[i] && !bnext->cnt && i-j>=4) { + // a..z span? Single digit numbers handled here too. TODO: utf8 + if (old[j+1]=='.' && old[j+2]=='.') { + bnext->commas[2] = old[j]; + bnext->commas[3] = old[j+3]; + k = 0; + if (old[j+4]=='}' || + (sscanf(old+j+4, "..%u}%n", bnext->commas+4, &k) && k)) + bnext->cnt = -1; + } + // 3..11 numeric span? + if (!bnext->cnt) { + for (k=0, j = 1+*bnext->commas; k<3; k++, j += x) + if (!sscanf(old+j, "..%u%n"+2*!k, bnext->commas+2+k, &x)) break; + if (old[j] == '}') bnext->cnt = -2; + } + // Increment goes in the right direction by at least 1 + if (bnext->cnt) { + if (!bnext->commas[4]) bnext->commas[4] = 1; + if ((bnext->commas[3]-bnext->commas[2]>0) != (bnext->commas[4]>0)) + bnext->commas[4] *= -1; + } + } + // discard unterminated span, or commaless span that wasn't x..y + if (!old[i] || !bnext->cnt) free(dlist_pop((blist == bnext) ? &blist : &bnext)); + // starting brace } else if (old[i] == '{') { dlist_add_nomalloc((void *)&blist, - (void *)(bb = xzalloc(sizeof(struct brace)+34*4))); + (void *)(bb = xzalloc(sizeof(struct sh_brace)+34*4))); bb->commas[0] = i; + // no active span? } else if (!bb) continue; - else if (bb && old[i] == ',') { + // add a comma to current span + else if (bb && old[i] == ',') { if (bb->cnt && !(bb->cnt&31)) { dlist_lpop(&blist); dlist_add_nomalloc((void *)&blist, - (void *)(bb = xrealloc(bb, sizeof(struct brace)+(bb->cnt+34)*4))); + (void *)(bb = xrealloc(bb, sizeof(struct sh_brace)+(bb->cnt+34)*4))); } bb->commas[++bb->cnt] = i; } @@ -1333,7 +1373,7 @@ static int expand_arg(struct sh_arg *arg, char *old, unsigned flags, if (!blist) return expand_arg_nobrace(arg, old, flags, delete, 0); // enclose entire range in top level brace. - (bstk = xzalloc(sizeof(struct brace)+8))->commas[1] = strlen(old)+1; + (bstk = xzalloc(sizeof(struct sh_brace)+8))->commas[1] = strlen(old)+1; bstk->commas[0] = -1; // loop through each combination @@ -1342,68 +1382,70 @@ static int expand_arg(struct sh_arg *arg, char *old, unsigned flags, // Brace expansion can't be longer than original string. Keep start to { s = ss = xmalloc(bstk->commas[1]); - // Append output from active braces (in "saved" list) - for (bb = blist; bb;) { + // Append output from active braces to string + for (bb = blist; bb; bb = (bnext == blist) ? 0 : bnext) { - // keep prefix and push self onto stack - if (bstk == bb) bstk = bstk->stack; // pop self - i = bstk->commas[bstk->idx]+1; - if (bstk->commas[bstk->cnt+1]>bb->commas[0]) + // If this brace already tip of stack, pop it. (We'll re-add in a moment.) + if (bstk == bb) bstk = bstk->stack; + // if bb is within bstk, save prefix text from bstk's "," to bb's "{" + if (brace_end(bstk)>bb->commas[0]) { + i = bstk->commas[bstk->idx]+1; s = stpncpy(s, old+i, bb->commas[0]-i); - - // pop sibling - if (bstk->commas[bstk->cnt+1]commas[0]) bstk = bstk->stack; - - bb->stack = bstk; // push + } + else bstk = bstk->stack; // bb past bstk so done with old bstk, pop it + // push self onto stack as active + bb->stack = bstk; bb->active = 1; bstk = bnext = bb; - // skip inactive spans from earlier or later commas + // Find next active range: skip inactive spans from earlier/later commas while ((bnext = (bnext->next==blist) ? 0 : bnext->next)) { - i = bnext->commas[0]; - // past end of this brace - if (i>bb->commas[bb->cnt+1]) break; + // past end of this brace (always true for a..b ranges) + if ((i = bnext->commas[0])>brace_end(bb)) break; - // in this brace but not this selection + // in this brace but not this section if (icommas[bb->idx] || i>bb->commas[bb->idx+1]) { bnext->active = 0; bnext->stack = 0; - // in this selection + // in this section } else break; } // is next span past this range? - if (!bnext || bnext->commas[0]>bb->commas[bb->idx+1]) { + if (!bnext || bb->cnt<0 || bnext->commas[0]>bb->commas[bb->idx+1]) { // output uninterrupted span - i = bb->commas[bstk->idx]+1; - s = stpncpy(s, old+i, bb->commas[bb->idx+1]-i); + if (bb->cnt<0) + s += sprintf(s, (bb->cnt==-1) ? "%c" : "%d", + bb->commas[2]+bb->commas[4]*bb->idx); + else { + i = bb->commas[bstk->idx]+1; + s = stpncpy(s, old+i, bb->commas[bb->idx+1]-i); + } // While not sibling, output tail and pop - while (!bnext || bnext->commas[0] > bstk->commas[bstk->cnt+1]) { + while (!bnext || bnext->commas[0]>brace_end(bstk)) { if (!(bb = bstk->stack)) break; - i = bstk->commas[bstk->cnt+1]+1; // start of span - j = bb->commas[bb->idx+1]; // enclosing comma span + i = brace_end(bstk)+1; // start of span + j = bb->commas[bb->idx+1]; // enclosing comma span (can't be a..b) while (bnext) { if (bnext->commas[0]commas[0];// sibling break; - } else if (bb->commas[bb->cnt+1]>bnext->commas[0]) + } else if (brace_end(bb)>bnext->commas[0]) bnext = (bnext->next == blist) ? 0 : bnext->next; else break; } s = stpncpy(s, old+i, j-i); // if next is sibling but parent _not_ a sibling, don't pop - if (bnext && bnext->commas[0]stack->commas[bstk->stack->cnt+1]) - break; - bstk = bstk->stack; + if (bnext && bnext->commas[0]prev; bb; bb = (bb == blist) ? 0 : bb->prev) { if (!bb->stack) continue; - else if (++bb->idx > bb->cnt) bb->idx = 0; + else if (bb->cnt<0) { + if (abs(bb->commas[2]-bb->commas[3]) < abs(++bb->idx*bb->commas[4])) + bb->idx = 0; + else break; + } else if (++bb->idx > bb->cnt) bb->idx = 0; else break; } -- cgit v1.2.3