diff options
Diffstat (limited to 'Src/subst.c')
| -rw-r--r-- | Src/subst.c | 125 |
1 files changed, 89 insertions, 36 deletions
diff --git a/Src/subst.c b/Src/subst.c index bbe7b3f07..28e306338 100644 --- a/Src/subst.c +++ b/Src/subst.c @@ -295,29 +295,86 @@ singsub(char **s) DPUTS(nonempty(&foo), "BUG: singsub() produced more than one word!"); } -/* Perform substitution on a single word. Unlike with singsub, the * - * result can have more than one word. A single word result is stored * - * in *s and *isarr is set to zero; otherwise *isarr is set to 1 and * - * the result is stored in *a. If `a' is zero a multiple word result is * - * joined using sep or the IFS parameter if sep is zero and the result * - * is returned in *s. The return value is true iff the expansion * - * resulted in an empty list. * - * The mult_isarr variable is used by paramsubst() to tell if it yields * - * an array. */ +/* Perform substitution on a single word, *s. Unlike with singsub(), the + * result can be more than one word. If split is non-zero, the string is + * first word-split using IFS, but only for non-quoted "whitespace" (as + * indicated by Dnull, Snull, Tick, Bnull, Inpar, and Outpar). + * + * If arg "a" was non-NULL _and_ the parsing set mult_isarr, the resulting + * strings are stored in *a (even for a 1-element array) and *isarr is set + * to 1. Otherwise, *isarr is set to 0, and the result is stored in *s, + * with any necessary joining of multiple elements using sep (which can be + * NULL to use IFS). The return value is true iff the expansion resulted + * in an empty list. + * + * The mult_isarr variable is used by paramsubst() to tell us if the + * substitutions yielded an array, but we will also set it if we split *s + * into multiple items (since that also yields an array). */ /**/ static int mult_isarr; /**/ static int -multsub(char **s, char ***a, int *isarr, UNUSED(char *sep)) +multsub(char **s, int split, char ***a, int *isarr, char *sep) { int l, omi = mult_isarr; - char **r, **p; + char **r, **p, *x = *s; local_list1(foo); mult_isarr = 0; - init_list1(foo, *s); + + if (split) { + for ( ; *x; x += l+1) { + char c = (l = *x == Meta) ? x[1] ^ 32 : *x; + if (!iwsep(c)) + break; + } + } + + init_list1(foo, x); + + if (split) { + LinkNode n = firstnode(&foo); + int inq = 0, inp = 0; + split = 0; /* use this to flag if we really split anything */ + for ( ; *x; x += l+1) { + char c = (l = *x == Meta) ? x[1] ^ 32 : *x; + if (!inq && !inp && isep(c)) { + *x = '\0'; + for (x += l+1; *x; x += l+1) { + c = (l = *x == Meta) ? x[1] ^ 32 : *x; + if (!isep(c)) + break; + } + if (!*x) + break; + insertlinknode(&foo, n, (void *)x), incnode(n); + split = 1; + } + switch (c) { + case Dnull: /* " */ + case Snull: /* ' */ + case Tick: /* ` (note: no Qtick!) */ + /* These always occur in unnested pairs. */ + inq = !inq; + break; + case Inpar: /* ( */ + inp++; + break; + case Outpar: /* ) */ + inp--; + break; + case Bnull: /* \ */ + case Bnullkeep: + /* The parser verified the following char's existence. */ + x += l+1; + l = *x == Meta; + break; + } + } + } + prefork(&foo, 0); if (errflag) { if (isarr) @@ -325,7 +382,10 @@ multsub(char **s, char ***a, int *isarr, UNUSED(char *sep)) mult_isarr = omi; return 0; } - if ((l = countlinknodes(&foo))) { + if (split) + mult_isarr = 1; + + if ((l = countlinknodes(&foo)) > 1 || (a && mult_isarr)) { p = r = hcalloc((l + 1) * sizeof(char*)); while (nonempty(&foo)) *p++ = (char *)ugetnode(&foo); @@ -345,7 +405,7 @@ multsub(char **s, char ***a, int *isarr, UNUSED(char *sep)) mult_isarr = omi; return 0; } - *s = sepjoin(r, NULL, 1); + *s = sepjoin(r, sep, 1); mult_isarr = omi; if (isarr) *isarr = 0; @@ -1457,7 +1517,7 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int ssub) * remove the aspar test and extract a value from an array, if * necessary, when we handle (P) lower down. */ - if (multsub(&val, (aspar ? NULL : &aval), &isarr, NULL) && quoted) { + if (multsub(&val, 0, (aspar ? NULL : &aval), &isarr, NULL) && quoted) { /* Empty quoted string --- treat as null string, not elided */ isarr = -1; aval = (char **) hcalloc(sizeof(char *)); @@ -1992,26 +2052,20 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int ssub) /* Fall Through! */ case '-': if (vunset) { + int ws = opts[SHWORDSPLIT]; val = dupstring(s); - /* - * This is not good enough for sh emulation! Sh would - * split unquoted substrings, yet not split quoted ones - * (except according to $@ rules); but this leaves the - * unquoted substrings unsplit, and other code below - * for spbreak splits even within the quoted substrings. - * - * TODO: I think multsub needs to be told enough to - * decide about splitting with spbreak at this point - * (and equally in the `=' handler below). Then - * we can turn off spbreak to avoid the join & split - * nastiness later. - * - * What we really want to do is make this look as - * if it were the result of an assignment from - * the same value, taking account of quoting. - */ - multsub(&val, (aspar ? NULL : &aval), &isarr, NULL); + /* If word-splitting is enabled, we ask multsub() to split + * the substituted string at unquoted whitespace. Then, we + * turn off spbreak so that no further splitting occurs. + * This allows a construct such as ${1+"$@"} to correctly + * keep its array splits, and weird constructs such as + * ${str+"one two" "3 2 1" foo "$str"} to only be split + * at the unquoted spaces. */ + opts[SHWORDSPLIT] = spbreak; + multsub(&val, spbreak && !aspar, (aspar ? NULL : &aval), &isarr, NULL); + opts[SHWORDSPLIT] = ws; copied = 1; + spbreak = 0; } break; case ':': @@ -2029,7 +2083,6 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int ssub) *idend = '\0'; val = dupstring(s); - isarr = 0; /* * TODO: this is one of those places where I don't * think we want to do the joining until later on. @@ -2037,9 +2090,9 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int ssub) * point and unset them. */ if (spsep || spbreak || !arrasg) - multsub(&val, NULL, NULL, sep); + multsub(&val, 0, NULL, &isarr, NULL); else - multsub(&val, &aval, &isarr, NULL); + multsub(&val, 0, &aval, &isarr, NULL); if (arrasg) { /* * This is an array assignment in a context |