aboutsummaryrefslogtreecommitdiff
path: root/bin/ksh/eval.c
diff options
context:
space:
mode:
Diffstat (limited to 'bin/ksh/eval.c')
-rw-r--r--bin/ksh/eval.c1340
1 files changed, 1340 insertions, 0 deletions
diff --git a/bin/ksh/eval.c b/bin/ksh/eval.c
new file mode 100644
index 0000000..7124fce
--- /dev/null
+++ b/bin/ksh/eval.c
@@ -0,0 +1,1340 @@
+/* $OpenBSD: eval.c,v 1.50 2016/03/05 12:30:17 czarkoff Exp $ */
+
+/*
+ * Expansion - quoting, separation, substitution, globbing
+ */
+
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "sh.h"
+
+/*
+ * string expansion
+ *
+ * first pass: quoting, IFS separation, ~, ${}, $() and $(()) substitution.
+ * second pass: alternation ({,}), filename expansion (*?[]).
+ */
+
+/* expansion generator state */
+typedef struct Expand {
+ /* int type; */ /* see expand() */
+ const char *str; /* string */
+ union {
+ const char **strv;/* string[] */
+ struct shf *shf;/* file */
+ } u; /* source */
+ struct tbl *var; /* variable in ${var..} */
+ short split; /* split "$@" / call waitlast $() */
+} Expand;
+
+#define XBASE 0 /* scanning original */
+#define XSUB 1 /* expanding ${} string */
+#define XARGSEP 2 /* ifs0 between "$*" */
+#define XARG 3 /* expanding $*, $@ */
+#define XCOM 4 /* expanding $() */
+#define XNULLSUB 5 /* "$@" when $# is 0 (don't generate word) */
+#define XSUBMID 6 /* middle of expanding ${} */
+
+/* States used for field splitting */
+#define IFS_WORD 0 /* word has chars (or quotes) */
+#define IFS_WS 1 /* have seen IFS white-space */
+#define IFS_NWS 2 /* have seen IFS non-white-space */
+
+static int varsub(Expand *, char *, char *, int *, int *);
+static int comsub(Expand *, char *);
+static char *trimsub(char *, char *, int);
+static void glob(char *, XPtrV *, int);
+static void globit(XString *, char **, char *, XPtrV *, int);
+static char *maybe_expand_tilde(char *, XString *, char **, int);
+static char *tilde(char *);
+static char *homedir(char *);
+#ifdef BRACE_EXPAND
+static void alt_expand(XPtrV *, char *, char *, char *, int);
+#endif
+
+/* compile and expand word */
+char *
+substitute(const char *cp, int f)
+{
+ struct source *s, *sold;
+
+ sold = source;
+ s = pushs(SWSTR, ATEMP);
+ s->start = s->str = cp;
+ source = s;
+ if (yylex(ONEWORD) != LWORD)
+ internal_errorf(1, "substitute");
+ source = sold;
+ afree(s, ATEMP);
+ return evalstr(yylval.cp, f);
+}
+
+/*
+ * expand arg-list
+ */
+char **
+eval(char **ap, int f)
+{
+ XPtrV w;
+
+ if (*ap == NULL)
+ return ap;
+ XPinit(w, 32);
+ XPput(w, NULL); /* space for shell name */
+ while (*ap != NULL)
+ expand(*ap++, &w, f);
+ XPput(w, NULL);
+ return (char **) XPclose(w) + 1;
+}
+
+/*
+ * expand string
+ */
+char *
+evalstr(char *cp, int f)
+{
+ XPtrV w;
+
+ XPinit(w, 1);
+ expand(cp, &w, f);
+ cp = (XPsize(w) == 0) ? null : (char*) *XPptrv(w);
+ XPfree(w);
+ return cp;
+}
+
+/*
+ * expand string - return only one component
+ * used from iosetup to expand redirection files
+ */
+char *
+evalonestr(char *cp, int f)
+{
+ XPtrV w;
+
+ XPinit(w, 1);
+ expand(cp, &w, f);
+ switch (XPsize(w)) {
+ case 0:
+ cp = null;
+ break;
+ case 1:
+ cp = (char*) *XPptrv(w);
+ break;
+ default:
+ cp = evalstr(cp, f&~DOGLOB);
+ break;
+ }
+ XPfree(w);
+ return cp;
+}
+
+/* for nested substitution: ${var:=$var2} */
+typedef struct SubType {
+ short stype; /* [=+-?%#] action after expanded word */
+ short base; /* begin position of expanded word */
+ short f; /* saved value of f (DOPAT, etc) */
+ struct tbl *var; /* variable for ${var..} */
+ short quote; /* saved value of quote (for ${..[%#]..}) */
+ struct SubType *prev; /* old type */
+ struct SubType *next; /* poped type (to avoid re-allocating) */
+} SubType;
+
+void
+expand(char *cp, /* input word */
+ XPtrV *wp, /* output words */
+ int f) /* DO* flags */
+{
+ int c = 0;
+ int type; /* expansion type */
+ int quote = 0; /* quoted */
+ XString ds; /* destination string */
+ char *dp, *sp; /* dest., source */
+ int fdo, word; /* second pass flags; have word */
+ int doblank; /* field splitting of parameter/command subst */
+ Expand x = {
+ /* expansion variables */
+ NULL, { NULL }, NULL, 0
+ };
+ SubType st_head, *st;
+ int newlines = 0; /* For trailing newlines in COMSUB */
+ int saw_eq, tilde_ok;
+ int make_magic;
+ size_t len;
+
+ if (cp == NULL)
+ internal_errorf(1, "expand(NULL)");
+ /* for alias, readonly, set, typeset commands */
+ if ((f & DOVACHECK) && is_wdvarassign(cp)) {
+ f &= ~(DOVACHECK|DOBLANK|DOGLOB|DOTILDE);
+ f |= DOASNTILDE;
+ }
+ if (Flag(FNOGLOB))
+ f &= ~DOGLOB;
+ if (Flag(FMARKDIRS))
+ f |= DOMARKDIRS;
+#ifdef BRACE_EXPAND
+ if (Flag(FBRACEEXPAND) && (f & DOGLOB))
+ f |= DOBRACE_;
+#endif /* BRACE_EXPAND */
+
+ Xinit(ds, dp, 128, ATEMP); /* init dest. string */
+ type = XBASE;
+ sp = cp;
+ fdo = 0;
+ saw_eq = 0;
+ tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0; /* must be 1/0 */
+ doblank = 0;
+ make_magic = 0;
+ word = (f&DOBLANK) ? IFS_WS : IFS_WORD;
+ st_head.next = NULL;
+ st = &st_head;
+
+ while (1) {
+ Xcheck(ds, dp);
+
+ switch (type) {
+ case XBASE: /* original prefixed string */
+ c = *sp++;
+ switch (c) {
+ case EOS:
+ c = 0;
+ break;
+ case CHAR:
+ c = *sp++;
+ break;
+ case QCHAR:
+ quote |= 2; /* temporary quote */
+ c = *sp++;
+ break;
+ case OQUOTE:
+ word = IFS_WORD;
+ tilde_ok = 0;
+ quote = 1;
+ continue;
+ case CQUOTE:
+ quote = 0;
+ continue;
+ case COMSUB:
+ tilde_ok = 0;
+ if (f & DONTRUNCOMMAND) {
+ word = IFS_WORD;
+ *dp++ = '$'; *dp++ = '(';
+ while (*sp != '\0') {
+ Xcheck(ds, dp);
+ *dp++ = *sp++;
+ }
+ *dp++ = ')';
+ } else {
+ type = comsub(&x, sp);
+ if (type == XCOM && (f&DOBLANK))
+ doblank++;
+ sp = strchr(sp, 0) + 1;
+ newlines = 0;
+ }
+ continue;
+ case EXPRSUB:
+ word = IFS_WORD;
+ tilde_ok = 0;
+ if (f & DONTRUNCOMMAND) {
+ *dp++ = '$'; *dp++ = '('; *dp++ = '(';
+ while (*sp != '\0') {
+ Xcheck(ds, dp);
+ *dp++ = *sp++;
+ }
+ *dp++ = ')'; *dp++ = ')';
+ } else {
+ struct tbl v;
+ char *p;
+
+ v.flag = DEFINED|ISSET|INTEGER;
+ v.type = 10; /* not default */
+ v.name[0] = '\0';
+ v_evaluate(&v, substitute(sp, 0),
+ KSH_UNWIND_ERROR, true);
+ sp = strchr(sp, 0) + 1;
+ for (p = str_val(&v); *p; ) {
+ Xcheck(ds, dp);
+ *dp++ = *p++;
+ }
+ }
+ continue;
+ case OSUBST: /* ${{#}var{:}[=+-?#%]word} */
+ /* format is:
+ * OSUBST [{x] plain-variable-part \0
+ * compiled-word-part CSUBST [}x]
+ * This is where all syntax checking gets done...
+ */
+ {
+ char *varname = ++sp; /* skip the { or x (}) */
+ int stype;
+ int slen = 0;
+
+ sp = strchr(sp, '\0') + 1; /* skip variable */
+ type = varsub(&x, varname, sp, &stype, &slen);
+ if (type < 0) {
+ char endc;
+ char *str, *end;
+
+ sp = varname - 2; /* restore sp */
+ end = (char *) wdscan(sp, CSUBST);
+ /* ({) the } or x is already skipped */
+ endc = *end;
+ *end = EOS;
+ str = snptreef(NULL, 64, "%S", sp);
+ *end = endc;
+ errorf("%s: bad substitution", str);
+ }
+ if (f&DOBLANK)
+ doblank++;
+ tilde_ok = 0;
+ if (type == XBASE) { /* expand? */
+ if (!st->next) {
+ SubType *newst;
+
+ newst = alloc(
+ sizeof(SubType), ATEMP);
+ newst->next = NULL;
+ newst->prev = st;
+ st->next = newst;
+ }
+ st = st->next;
+ st->stype = stype;
+ st->base = Xsavepos(ds, dp);
+ st->f = f;
+ st->var = x.var;
+ st->quote = quote;
+ /* skip qualifier(s) */
+ if (stype)
+ sp += slen;
+ switch (stype & 0x7f) {
+ case '#':
+ case '%':
+ /* ! DOBLANK,DOBRACE_,DOTILDE */
+ f = DOPAT | (f&DONTRUNCOMMAND) |
+ DOTEMP_;
+ quote = 0;
+ /* Prepend open pattern (so |
+ * in a trim will work as
+ * expected)
+ */
+ *dp++ = MAGIC;
+ *dp++ = '@' + 0x80;
+ break;
+ case '=':
+ /* Enabling tilde expansion
+ * after :'s here is
+ * non-standard ksh, but is
+ * consistent with rules for
+ * other assignments. Not
+ * sure what POSIX thinks of
+ * this.
+ * Not doing tilde expansion
+ * for integer variables is a
+ * non-POSIX thing - makes
+ * sense though, since ~ is
+ * a arithmetic operator.
+ */
+ if (!(x.var->flag & INTEGER))
+ f |= DOASNTILDE|DOTILDE;
+ f |= DOTEMP_;
+ /* These will be done after the
+ * value has been assigned.
+ */
+ f &= ~(DOBLANK|DOGLOB|DOBRACE_);
+ tilde_ok = 1;
+ break;
+ case '?':
+ f &= ~DOBLANK;
+ f |= DOTEMP_;
+ /* FALLTHROUGH */
+ default:
+ /* Enable tilde expansion */
+ tilde_ok = 1;
+ f |= DOTILDE;
+ }
+ } else
+ /* skip word */
+ sp = (char *) wdscan(sp, CSUBST);
+ continue;
+ }
+ case CSUBST: /* only get here if expanding word */
+ sp++; /* ({) skip the } or x */
+ tilde_ok = 0; /* in case of ${unset:-} */
+ *dp = '\0';
+ quote = st->quote;
+ f = st->f;
+ if (f&DOBLANK)
+ doblank--;
+ switch (st->stype&0x7f) {
+ case '#':
+ case '%':
+ /* Append end-pattern */
+ *dp++ = MAGIC; *dp++ = ')'; *dp = '\0';
+ dp = Xrestpos(ds, dp, st->base);
+ /* Must use st->var since calling
+ * global would break things
+ * like x[i+=1].
+ */
+ x.str = trimsub(str_val(st->var),
+ dp, st->stype);
+ if (x.str[0] != '\0' || st->quote)
+ type = XSUB;
+ else
+ type = XNULLSUB;
+ if (f&DOBLANK)
+ doblank++;
+ st = st->prev;
+ continue;
+ case '=':
+ /* Restore our position and substitute
+ * the value of st->var (may not be
+ * the assigned value in the presence
+ * of integer/right-adj/etc attributes).
+ */
+ dp = Xrestpos(ds, dp, st->base);
+ /* Must use st->var since calling
+ * global would cause with things
+ * like x[i+=1] to be evaluated twice.
+ */
+ /* Note: not exported by FEXPORT
+ * in at&t ksh.
+ */
+ /* XXX POSIX says readonly is only
+ * fatal for special builtins (setstr
+ * does readonly check).
+ */
+ len = strlen(dp) + 1;
+ setstr(st->var,
+ debunk(alloc(len, ATEMP),
+ dp, len), KSH_UNWIND_ERROR);
+ x.str = str_val(st->var);
+ type = XSUB;
+ if (f&DOBLANK)
+ doblank++;
+ st = st->prev;
+ continue;
+ case '?':
+ {
+ char *s = Xrestpos(ds, dp, st->base);
+
+ errorf("%s: %s", st->var->name,
+ dp == s ?
+ "parameter null or not set" :
+ (debunk(s, s, strlen(s) + 1), s));
+ }
+ }
+ st = st->prev;
+ type = XBASE;
+ continue;
+
+ case OPAT: /* open pattern: *(foo|bar) */
+ /* Next char is the type of pattern */
+ make_magic = 1;
+ c = *sp++ + 0x80;
+ break;
+
+ case SPAT: /* pattern separator (|) */
+ make_magic = 1;
+ c = '|';
+ break;
+
+ case CPAT: /* close pattern */
+ make_magic = 1;
+ c = /*(*/ ')';
+ break;
+ }
+ break;
+
+ case XNULLSUB:
+ /* Special case for "$@" (and "${foo[@]}") - no
+ * word is generated if $# is 0 (unless there is
+ * other stuff inside the quotes).
+ */
+ type = XBASE;
+ if (f&DOBLANK) {
+ doblank--;
+ /* not really correct: x=; "$x$@" should
+ * generate a null argument and
+ * set A; "${@:+}" shouldn't.
+ */
+ if (dp == Xstring(ds, dp))
+ word = IFS_WS;
+ }
+ continue;
+
+ case XSUB:
+ case XSUBMID:
+ if ((c = *x.str++) == 0) {
+ type = XBASE;
+ if (f&DOBLANK)
+ doblank--;
+ continue;
+ }
+ break;
+
+ case XARGSEP:
+ type = XARG;
+ quote = 1;
+ case XARG:
+ if ((c = *x.str++) == '\0') {
+ /* force null words to be created so
+ * set -- '' 2 ''; foo "$@" will do
+ * the right thing
+ */
+ if (quote && x.split)
+ word = IFS_WORD;
+ if ((x.str = *x.u.strv++) == NULL) {
+ type = XBASE;
+ if (f&DOBLANK)
+ doblank--;
+ continue;
+ }
+ c = ifs0;
+ if (c == 0) {
+ if (quote && !x.split)
+ continue;
+ c = ' ';
+ }
+ if (quote && x.split) {
+ /* terminate word for "$@" */
+ type = XARGSEP;
+ quote = 0;
+ }
+ }
+ break;
+
+ case XCOM:
+ if (x.u.shf == NULL) /* $(< ...) failed, fake EOF */
+ c = EOF;
+ else if (newlines) { /* Spit out saved nl's */
+ c = '\n';
+ --newlines;
+ } else {
+ while ((c = shf_getc(x.u.shf)) == 0 || c == '\n')
+ if (c == '\n')
+ newlines++; /* Save newlines */
+ if (newlines && c != EOF) {
+ shf_ungetc(c, x.u.shf);
+ c = '\n';
+ --newlines;
+ }
+ }
+ if (c == EOF) {
+ newlines = 0;
+ if (x.u.shf != NULL)
+ shf_close(x.u.shf);
+ if (x.split)
+ subst_exstat = waitlast();
+ else
+ subst_exstat = (x.u.shf == NULL);
+ type = XBASE;
+ if (f&DOBLANK)
+ doblank--;
+ continue;
+ }
+ break;
+ }
+
+ /* check for end of word or IFS separation */
+ if (c == 0 || (!quote && (f & DOBLANK) && doblank &&
+ !make_magic && ctype(c, C_IFS))) {
+ /* How words are broken up:
+ * | value of c
+ * word | ws nws 0
+ * -----------------------------------
+ * IFS_WORD w/WS w/NWS w
+ * IFS_WS -/WS w/NWS -
+ * IFS_NWS -/NWS w/NWS w
+ * (w means generate a word)
+ * Note that IFS_NWS/0 generates a word (at&t ksh
+ * doesn't do this, but POSIX does).
+ */
+ if (word == IFS_WORD ||
+ (!ctype(c, C_IFSWS) && c && word == IFS_NWS)) {
+ char *p;
+
+ *dp++ = '\0';
+ p = Xclose(ds, dp);
+#ifdef BRACE_EXPAND
+ if (fdo & DOBRACE_)
+ /* also does globbing */
+ alt_expand(wp, p, p,
+ p + Xlength(ds, (dp - 1)),
+ fdo | (f & DOMARKDIRS));
+ else
+#endif /* BRACE_EXPAND */
+ if (fdo & DOGLOB)
+ glob(p, wp, f & DOMARKDIRS);
+ else if ((f & DOPAT) || !(fdo & DOMAGIC_))
+ XPput(*wp, p);
+ else
+ XPput(*wp, debunk(p, p, strlen(p) + 1));
+ fdo = 0;
+ saw_eq = 0;
+ tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0;
+ if (c != 0)
+ Xinit(ds, dp, 128, ATEMP);
+ }
+ if (c == 0)
+ return;
+ if (word != IFS_NWS)
+ word = ctype(c, C_IFSWS) ? IFS_WS : IFS_NWS;
+ } else {
+ if (type == XSUB) {
+ if (word == IFS_NWS &&
+ Xlength(ds, dp) == 0) {
+ char *p;
+
+ if ((p = strdup("")) == NULL)
+ internal_errorf(1, "unable "
+ "to allocate memory");
+ XPput(*wp, p);
+ }
+ type = XSUBMID;
+ }
+
+ /* age tilde_ok info - ~ code tests second bit */
+ tilde_ok <<= 1;
+ /* mark any special second pass chars */
+ if (!quote)
+ switch (c) {
+ case '[':
+ case '!':
+ case '-':
+ case ']':
+ /* For character classes - doesn't hurt
+ * to have magic !,-,]'s outside of
+ * [...] expressions.
+ */
+ if (f & (DOPAT | DOGLOB)) {
+ fdo |= DOMAGIC_;
+ if (c == '[')
+ fdo |= f & DOGLOB;
+ *dp++ = MAGIC;
+ }
+ break;
+ case '*':
+ case '?':
+ if (f & (DOPAT | DOGLOB)) {
+ fdo |= DOMAGIC_ | (f & DOGLOB);
+ *dp++ = MAGIC;
+ }
+ break;
+#ifdef BRACE_EXPAND
+ case OBRACE:
+ case ',':
+ case CBRACE:
+ if ((f & DOBRACE_) && (c == OBRACE ||
+ (fdo & DOBRACE_))) {
+ fdo |= DOBRACE_|DOMAGIC_;
+ *dp++ = MAGIC;
+ }
+ break;
+#endif /* BRACE_EXPAND */
+ case '=':
+ /* Note first unquoted = for ~ */
+ if (!(f & DOTEMP_) && !saw_eq) {
+ saw_eq = 1;
+ tilde_ok = 1;
+ }
+ break;
+ case ':': /* : */
+ /* Note unquoted : for ~ */
+ if (!(f & DOTEMP_) && (f & DOASNTILDE))
+ tilde_ok = 1;
+ break;
+ case '~':
+ /* tilde_ok is reset whenever
+ * any of ' " $( $(( ${ } are seen.
+ * Note that tilde_ok must be preserved
+ * through the sequence ${A=a=}~
+ */
+ if (type == XBASE &&
+ (f & (DOTILDE|DOASNTILDE)) &&
+ (tilde_ok & 2)) {
+ char *p, *dp_x;
+
+ dp_x = dp;
+ p = maybe_expand_tilde(sp,
+ &ds, &dp_x,
+ f & DOASNTILDE);
+ if (p) {
+ if (dp != dp_x)
+ word = IFS_WORD;
+ dp = dp_x;
+ sp = p;
+ continue;
+ }
+ }
+ break;
+ }
+ else
+ quote &= ~2; /* undo temporary */
+
+ if (make_magic) {
+ make_magic = 0;
+ fdo |= DOMAGIC_ | (f & DOGLOB);
+ *dp++ = MAGIC;
+ } else if (ISMAGIC(c)) {
+ fdo |= DOMAGIC_;
+ *dp++ = MAGIC;
+ }
+ *dp++ = c; /* save output char */
+ word = IFS_WORD;
+ }
+ }
+}
+
+/*
+ * Prepare to generate the string returned by ${} substitution.
+ */
+static int
+varsub(Expand *xp, char *sp, char *word,
+ int *stypep, /* becomes qualifier type */
+ int *slenp) /* " " len (=, :=, etc.) valid iff *stypep != 0 */
+{
+ int c;
+ int state; /* next state: XBASE, XARG, XSUB, XNULLSUB */
+ int stype; /* substitution type */
+ int slen;
+ char *p;
+ struct tbl *vp;
+ int zero_ok = 0;
+
+ if (sp[0] == '\0') /* Bad variable name */
+ return -1;
+
+ xp->var = NULL;
+
+ /* ${#var}, string length or array size */
+ if (sp[0] == '#' && (c = sp[1]) != '\0') {
+ /* Can't have any modifiers for ${#...} */
+ if (*word != CSUBST)
+ return -1;
+ sp++;
+ /* Check for size of array */
+ if ((p=strchr(sp,'[')) && (p[1]=='*'||p[1]=='@') && p[2]==']') {
+ int n = 0;
+
+ vp = global(arrayname(sp));
+ if (vp->flag & (ISSET|ARRAY))
+ zero_ok = 1;
+ for (; vp; vp = vp->u.array)
+ if (vp->flag & ISSET)
+ n++;
+ c = n; /* ksh88/ksh93 go for number, not max index */
+ } else if (c == '*' || c == '@')
+ c = genv->loc->argc;
+ else {
+ p = str_val(global(sp));
+ zero_ok = p != null;
+ c = strlen(p);
+ }
+ if (Flag(FNOUNSET) && c == 0 && !zero_ok)
+ errorf("%s: parameter not set", sp);
+ *stypep = 0; /* unqualified variable/string substitution */
+ xp->str = str_save(ulton((unsigned long)c, 10), ATEMP);
+ return XSUB;
+ }
+
+ /* Check for qualifiers in word part */
+ stype = 0;
+ c = word[slen = 0] == CHAR ? word[1] : 0;
+ if (c == ':') {
+ slen += 2;
+ stype = 0x80;
+ c = word[slen + 0] == CHAR ? word[slen + 1] : 0;
+ }
+ if (ctype(c, C_SUBOP1)) {
+ slen += 2;
+ stype |= c;
+ } else if (ctype(c, C_SUBOP2)) { /* Note: ksh88 allows :%, :%%, etc */
+ slen += 2;
+ stype = c;
+ if (word[slen + 0] == CHAR && c == word[slen + 1]) {
+ stype |= 0x80;
+ slen += 2;
+ }
+ } else if (stype) /* : is not ok */
+ return -1;
+ if (!stype && *word != CSUBST)
+ return -1;
+ *stypep = stype;
+ *slenp = slen;
+
+ c = sp[0];
+ if (c == '*' || c == '@') {
+ switch (stype & 0x7f) {
+ case '=': /* can't assign to a vector */
+ case '%': /* can't trim a vector (yet) */
+ case '#':
+ return -1;
+ }
+ if (genv->loc->argc == 0) {
+ xp->str = null;
+ xp->var = global(sp);
+ state = c == '@' ? XNULLSUB : XSUB;
+ } else {
+ xp->u.strv = (const char **) genv->loc->argv + 1;
+ xp->str = *xp->u.strv++;
+ xp->split = c == '@'; /* $@ */
+ state = XARG;
+ }
+ zero_ok = 1; /* exempt "$@" and "$*" from 'set -u' */
+ } else {
+ if ((p=strchr(sp,'[')) && (p[1]=='*'||p[1]=='@') && p[2]==']') {
+ XPtrV wv;
+
+ switch (stype & 0x7f) {
+ case '=': /* can't assign to a vector */
+ case '%': /* can't trim a vector (yet) */
+ case '#':
+ case '?':
+ return -1;
+ }
+ XPinit(wv, 32);
+ vp = global(arrayname(sp));
+ for (; vp; vp = vp->u.array) {
+ if (!(vp->flag&ISSET))
+ continue;
+ XPput(wv, str_val(vp));
+ }
+ if (XPsize(wv) == 0) {
+ xp->str = null;
+ state = p[1] == '@' ? XNULLSUB : XSUB;
+ XPfree(wv);
+ } else {
+ XPput(wv, 0);
+ xp->u.strv = (const char **) XPptrv(wv);
+ xp->str = *xp->u.strv++;
+ xp->split = p[1] == '@'; /* ${foo[@]} */
+ state = XARG;
+ }
+ } else {
+ /* Can't assign things like $! or $1 */
+ if ((stype & 0x7f) == '=' &&
+ (ctype(*sp, C_VAR1) || digit(*sp)))
+ return -1;
+ xp->var = global(sp);
+ xp->str = str_val(xp->var);
+ state = XSUB;
+ }
+ }
+
+ c = stype&0x7f;
+ /* test the compiler's code generator */
+ if (ctype(c, C_SUBOP2) ||
+ (((stype&0x80) ? *xp->str=='\0' : xp->str==null) ? /* undef? */
+ c == '=' || c == '-' || c == '?' : c == '+'))
+ state = XBASE; /* expand word instead of variable value */
+ if (Flag(FNOUNSET) && xp->str == null && !zero_ok &&
+ (ctype(c, C_SUBOP2) || (state != XBASE && c != '+')))
+ errorf("%s: parameter not set", sp);
+ return state;
+}
+
+/*
+ * Run the command in $(...) and read its output.
+ */
+static int
+comsub(Expand *xp, char *cp)
+{
+ Source *s, *sold;
+ struct op *t;
+ struct shf *shf;
+
+ s = pushs(SSTRING, ATEMP);
+ s->start = s->str = cp;
+ sold = source;
+ t = compile(s);
+ afree(s, ATEMP);
+ source = sold;
+
+ if (t == NULL)
+ return XBASE;
+
+ if (t != NULL && t->type == TCOM && /* $(<file) */
+ *t->args == NULL && *t->vars == NULL && t->ioact != NULL) {
+ struct ioword *io = *t->ioact;
+ char *name;
+
+ if ((io->flag&IOTYPE) != IOREAD)
+ errorf("funny $() command: %s",
+ snptreef(NULL, 32, "%R", io));
+ shf = shf_open(name = evalstr(io->name, DOTILDE), O_RDONLY, 0,
+ SHF_MAPHI|SHF_CLEXEC);
+ if (shf == NULL)
+ warningf(!Flag(FTALKING),
+ "%s: cannot open $(<) input", name);
+ xp->split = 0; /* no waitlast() */
+ } else {
+ int ofd1, pv[2];
+ openpipe(pv);
+ shf = shf_fdopen(pv[0], SHF_RD, NULL);
+ ofd1 = savefd(1);
+ if (pv[1] != 1) {
+ ksh_dup2(pv[1], 1, false);
+ close(pv[1]);
+ }
+ execute(t, XFORK|XXCOM|XPIPEO, NULL);
+ restfd(1, ofd1);
+ startlast();
+ xp->split = 1; /* waitlast() */
+ }
+
+ xp->u.shf = shf;
+ return XCOM;
+}
+
+/*
+ * perform #pattern and %pattern substitution in ${}
+ */
+
+static char *
+trimsub(char *str, char *pat, int how)
+{
+ char *end = strchr(str, 0);
+ char *p, c;
+
+ switch (how&0xff) { /* UCHAR_MAX maybe? */
+ case '#': /* shortest at beginning */
+ for (p = str; p <= end; p++) {
+ c = *p; *p = '\0';
+ if (gmatch(str, pat, false)) {
+ *p = c;
+ return p;
+ }
+ *p = c;
+ }
+ break;
+ case '#'|0x80: /* longest match at beginning */
+ for (p = end; p >= str; p--) {
+ c = *p; *p = '\0';
+ if (gmatch(str, pat, false)) {
+ *p = c;
+ return p;
+ }
+ *p = c;
+ }
+ break;
+ case '%': /* shortest match at end */
+ for (p = end; p >= str; p--) {
+ if (gmatch(p, pat, false))
+ return str_nsave(str, p - str, ATEMP);
+ }
+ break;
+ case '%'|0x80: /* longest match at end */
+ for (p = str; p <= end; p++) {
+ if (gmatch(p, pat, false))
+ return str_nsave(str, p - str, ATEMP);
+ }
+ break;
+ }
+
+ return str; /* no match, return string */
+}
+
+/*
+ * glob
+ * Name derived from V6's /etc/glob, the program that expanded filenames.
+ */
+
+/* XXX cp not const 'cause slashes are temporarily replaced with nulls... */
+static void
+glob(char *cp, XPtrV *wp, int markdirs)
+{
+ int oldsize = XPsize(*wp);
+
+ if (glob_str(cp, wp, markdirs) == 0)
+ XPput(*wp, debunk(cp, cp, strlen(cp) + 1));
+ else
+ qsortp(XPptrv(*wp) + oldsize, (size_t)(XPsize(*wp) - oldsize),
+ xstrcmp);
+}
+
+#define GF_NONE 0
+#define GF_EXCHECK BIT(0) /* do existence check on file */
+#define GF_GLOBBED BIT(1) /* some globbing has been done */
+#define GF_MARKDIR BIT(2) /* add trailing / to directories */
+
+/* Apply file globbing to cp and store the matching files in wp. Returns
+ * the number of matches found.
+ */
+int
+glob_str(char *cp, XPtrV *wp, int markdirs)
+{
+ int oldsize = XPsize(*wp);
+ XString xs;
+ char *xp;
+
+ Xinit(xs, xp, 256, ATEMP);
+ globit(&xs, &xp, cp, wp, markdirs ? GF_MARKDIR : GF_NONE);
+ Xfree(xs, xp);
+
+ return XPsize(*wp) - oldsize;
+}
+
+static void
+globit(XString *xs, /* dest string */
+ char **xpp, /* ptr to dest end */
+ char *sp, /* source path */
+ XPtrV *wp, /* output list */
+ int check) /* GF_* flags */
+{
+ char *np; /* next source component */
+ char *xp = *xpp;
+ char *se;
+ char odirsep;
+
+ /* This to allow long expansions to be interrupted */
+ intrcheck();
+
+ if (sp == NULL) { /* end of source path */
+ /* We only need to check if the file exists if a pattern
+ * is followed by a non-pattern (eg, foo*x/bar; no check
+ * is needed for foo* since the match must exist) or if
+ * any patterns were expanded and the markdirs option is set.
+ * Symlinks make things a bit tricky...
+ */
+ if ((check & GF_EXCHECK) ||
+ ((check & GF_MARKDIR) && (check & GF_GLOBBED))) {
+#define stat_check() (stat_done ? stat_done : \
+ (stat_done = stat(Xstring(*xs, xp), &statb) < 0 \
+ ? -1 : 1))
+ struct stat lstatb, statb;
+ int stat_done = 0; /* -1: failed, 1 ok */
+
+ if (lstat(Xstring(*xs, xp), &lstatb) < 0)
+ return;
+ /* special case for systems which strip trailing
+ * slashes from regular files (eg, /etc/passwd/).
+ * SunOS 4.1.3 does this...
+ */
+ if ((check & GF_EXCHECK) && xp > Xstring(*xs, xp) &&
+ xp[-1] == '/' && !S_ISDIR(lstatb.st_mode) &&
+ (!S_ISLNK(lstatb.st_mode) ||
+ stat_check() < 0 || !S_ISDIR(statb.st_mode)))
+ return;
+ /* Possibly tack on a trailing / if there isn't already
+ * one and if the file is a directory or a symlink to a
+ * directory
+ */
+ if (((check & GF_MARKDIR) && (check & GF_GLOBBED)) &&
+ xp > Xstring(*xs, xp) && xp[-1] != '/' &&
+ (S_ISDIR(lstatb.st_mode) ||
+ (S_ISLNK(lstatb.st_mode) && stat_check() > 0 &&
+ S_ISDIR(statb.st_mode)))) {
+ *xp++ = '/';
+ *xp = '\0';
+ }
+ }
+ XPput(*wp, str_nsave(Xstring(*xs, xp), Xlength(*xs, xp), ATEMP));
+ return;
+ }
+
+ if (xp > Xstring(*xs, xp))
+ *xp++ = '/';
+ while (*sp == '/') {
+ Xcheck(*xs, xp);
+ *xp++ = *sp++;
+ }
+ np = strchr(sp, '/');
+ if (np != NULL) {
+ se = np;
+ odirsep = *np; /* don't assume '/', can be multiple kinds */
+ *np++ = '\0';
+ } else {
+ odirsep = '\0'; /* keep gcc quiet */
+ se = sp + strlen(sp);
+ }
+
+
+ /* Check if sp needs globbing - done to avoid pattern checks for strings
+ * containing MAGIC characters, open ['s without the matching close ],
+ * etc. (otherwise opendir() will be called which may fail because the
+ * directory isn't readable - if no globbing is needed, only execute
+ * permission should be required (as per POSIX)).
+ */
+ if (!has_globbing(sp, se)) {
+ XcheckN(*xs, xp, se - sp + 1);
+ debunk(xp, sp, Xnleft(*xs, xp));
+ xp += strlen(xp);
+ *xpp = xp;
+ globit(xs, xpp, np, wp, check);
+ } else {
+ DIR *dirp;
+ struct dirent *d;
+ char *name;
+ int len;
+ int prefix_len;
+
+ /* xp = *xpp; copy_non_glob() may have re-alloc'd xs */
+ *xp = '\0';
+ prefix_len = Xlength(*xs, xp);
+ dirp = opendir(prefix_len ? Xstring(*xs, xp) : ".");
+ if (dirp == NULL)
+ goto Nodir;
+ while ((d = readdir(dirp)) != NULL) {
+ name = d->d_name;
+ if (name[0] == '.' &&
+ (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
+ continue; /* always ignore . and .. */
+ if ((*name == '.' && *sp != '.') ||
+ !gmatch(name, sp, true))
+ continue;
+
+ len = strlen(d->d_name) + 1;
+ XcheckN(*xs, xp, len);
+ memcpy(xp, name, len);
+ *xpp = xp + len - 1;
+ globit(xs, xpp, np, wp,
+ (check & GF_MARKDIR) | GF_GLOBBED
+ | (np ? GF_EXCHECK : GF_NONE));
+ xp = Xstring(*xs, xp) + prefix_len;
+ }
+ closedir(dirp);
+ Nodir:;
+ }
+
+ if (np != NULL)
+ *--np = odirsep;
+}
+
+#if 0
+/* Check if p contains something that needs globbing; if it does, 0 is
+ * returned; if not, p is copied into xs/xp after stripping any MAGICs
+ */
+static int copy_non_glob(XString *xs, char **xpp, char *p);
+static int
+copy_non_glob(XString *xs, char **xpp, char *p)
+{
+ char *xp;
+ int len = strlen(p);
+
+ XcheckN(*xs, *xpp, len);
+ xp = *xpp;
+ for (; *p; p++) {
+ if (ISMAGIC(*p)) {
+ int c = *++p;
+
+ if (c == '*' || c == '?')
+ return 0;
+ if (*p == '[') {
+ char *q = p + 1;
+
+ if (ISMAGIC(*q) && q[1] == '!')
+ q += 2;
+ if (ISMAGIC(*q) && q[1] == ']')
+ q += 2;
+ for (; *q; q++)
+ if (ISMAGIC(*q) && *++q == ']')
+ return 0;
+ /* pass a literal [ through */
+ }
+ /* must be a MAGIC-MAGIC, or MAGIC-!, MAGIC--, etc. */
+ }
+ *xp++ = *p;
+ }
+ *xp = '\0';
+ *xpp = xp;
+ return 1;
+}
+#endif /* 0 */
+
+/* remove MAGIC from string */
+char *
+debunk(char *dp, const char *sp, size_t dlen)
+{
+ char *d, *s;
+
+ if ((s = strchr(sp, MAGIC))) {
+ if (s - sp >= dlen)
+ return dp;
+ memcpy(dp, sp, s - sp);
+ for (d = dp + (s - sp); *s && (d - dp < dlen); s++)
+ if (!ISMAGIC(*s) || !(*++s & 0x80) ||
+ !strchr("*+?@! ", *s & 0x7f))
+ *d++ = *s;
+ else {
+ /* extended pattern operators: *+?@! */
+ if ((*s & 0x7f) != ' ')
+ *d++ = *s & 0x7f;
+ if (d - dp < dlen)
+ *d++ = '(';
+ }
+ *d = '\0';
+ } else if (dp != sp)
+ strlcpy(dp, sp, dlen);
+ return dp;
+}
+
+/* Check if p is an unquoted name, possibly followed by a / or :. If so
+ * puts the expanded version in *dcp,dp and returns a pointer in p just
+ * past the name, otherwise returns 0.
+ */
+static char *
+maybe_expand_tilde(char *p, XString *dsp, char **dpp, int isassign)
+{
+ XString ts;
+ char *dp = *dpp;
+ char *tp, *r;
+
+ Xinit(ts, tp, 16, ATEMP);
+ /* : only for DOASNTILDE form */
+ while (p[0] == CHAR && p[1] != '/' && (!isassign || p[1] != ':'))
+ {
+ Xcheck(ts, tp);
+ *tp++ = p[1];
+ p += 2;
+ }
+ *tp = '\0';
+ r = (p[0] == EOS || p[0] == CHAR || p[0] == CSUBST) ?
+ tilde(Xstring(ts, tp)) : NULL;
+ Xfree(ts, tp);
+ if (r) {
+ while (*r) {
+ Xcheck(*dsp, dp);
+ if (ISMAGIC(*r))
+ *dp++ = MAGIC;
+ *dp++ = *r++;
+ }
+ *dpp = dp;
+ r = p;
+ }
+ return r;
+}
+
+/*
+ * tilde expansion
+ *
+ * based on a version by Arnold Robbins
+ */
+
+static char *
+tilde(char *cp)
+{
+ char *dp;
+
+ if (cp[0] == '\0')
+ dp = str_val(global("HOME"));
+ else if (cp[0] == '+' && cp[1] == '\0')
+ dp = str_val(global("PWD"));
+ else if (cp[0] == '-' && cp[1] == '\0')
+ dp = str_val(global("OLDPWD"));
+ else
+ dp = homedir(cp);
+ /* If HOME, PWD or OLDPWD are not set, don't expand ~ */
+ if (dp == null)
+ dp = NULL;
+ return dp;
+}
+
+/*
+ * map userid to user's home directory.
+ * note that 4.3's getpw adds more than 6K to the shell,
+ * and the YP version probably adds much more.
+ * we might consider our own version of getpwnam() to keep the size down.
+ */
+
+static char *
+homedir(char *name)
+{
+ struct tbl *ap;
+
+ ap = ktenter(&homedirs, name, hash(name));
+ if (!(ap->flag & ISSET)) {
+ struct passwd *pw;
+
+ pw = getpwnam(name);
+ if (pw == NULL)
+ return NULL;
+ ap->val.s = str_save(pw->pw_dir, APERM);
+ ap->flag |= DEFINED|ISSET|ALLOC;
+ }
+ return ap->val.s;
+}
+
+#ifdef BRACE_EXPAND
+static void
+alt_expand(XPtrV *wp, char *start, char *exp_start, char *end, int fdo)
+{
+ int count = 0;
+ char *brace_start, *brace_end, *comma = NULL;
+ char *field_start;
+ char *p;
+
+ /* search for open brace */
+ for (p = exp_start; (p = strchr(p, MAGIC)) && p[1] != OBRACE; p += 2)
+ ;
+ brace_start = p;
+
+ /* find matching close brace, if any */
+ if (p) {
+ comma = NULL;
+ count = 1;
+ for (p += 2; *p && count; p++) {
+ if (ISMAGIC(*p)) {
+ if (*++p == OBRACE)
+ count++;
+ else if (*p == CBRACE)
+ --count;
+ else if (*p == ',' && count == 1)
+ comma = p;
+ }
+ }
+ }
+ /* no valid expansions... */
+ if (!p || count != 0) {
+ /* Note that given a{{b,c} we do not expand anything (this is
+ * what at&t ksh does. This may be changed to do the {b,c}
+ * expansion. }
+ */
+ if (fdo & DOGLOB)
+ glob(start, wp, fdo & DOMARKDIRS);
+ else
+ XPput(*wp, debunk(start, start, end - start));
+ return;
+ }
+ brace_end = p;
+ if (!comma) {
+ alt_expand(wp, start, brace_end, end, fdo);
+ return;
+ }
+
+ /* expand expression */
+ field_start = brace_start + 2;
+ count = 1;
+ for (p = brace_start + 2; p != brace_end; p++) {
+ if (ISMAGIC(*p)) {
+ if (*++p == OBRACE)
+ count++;
+ else if ((*p == CBRACE && --count == 0) ||
+ (*p == ',' && count == 1)) {
+ char *new;
+ int l1, l2, l3;
+
+ l1 = brace_start - start;
+ l2 = (p - 1) - field_start;
+ l3 = end - brace_end;
+ new = alloc(l1 + l2 + l3 + 1, ATEMP);
+ memcpy(new, start, l1);
+ memcpy(new + l1, field_start, l2);
+ memcpy(new + l1 + l2, brace_end, l3);
+ new[l1 + l2 + l3] = '\0';
+ alt_expand(wp, new, new + l1,
+ new + l1 + l2 + l3, fdo);
+ field_start = p + 1;
+ }
+ }
+ }
+ return;
+}
+#endif /* BRACE_EXPAND */