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-rw-r--r--bin/ksh/var.c1209
1 files changed, 1209 insertions, 0 deletions
diff --git a/bin/ksh/var.c b/bin/ksh/var.c
new file mode 100644
index 0000000..750ea59
--- /dev/null
+++ b/bin/ksh/var.c
@@ -0,0 +1,1209 @@
+/* $OpenBSD: var.c,v 1.55 2015/12/30 09:07:00 tedu Exp $ */
+
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "sh.h"
+
+/*
+ * Variables
+ *
+ * WARNING: unreadable code, needs a rewrite
+ *
+ * if (flag&INTEGER), val.i contains integer value, and type contains base.
+ * otherwise, (val.s + type) contains string value.
+ * if (flag&EXPORT), val.s contains "name=value" for E-Z exporting.
+ */
+static struct tbl vtemp;
+static struct table specials;
+static char *formatstr(struct tbl *, const char *);
+static void export(struct tbl *, const char *);
+static int special(const char *);
+static void unspecial(const char *);
+static void getspec(struct tbl *);
+static void setspec(struct tbl *);
+static void unsetspec(struct tbl *);
+static struct tbl *arraysearch(struct tbl *, int);
+
+/*
+ * create a new block for function calls and simple commands
+ * assume caller has allocated and set up genv->loc
+ */
+void
+newblock(void)
+{
+ struct block *l;
+ static char *const empty[] = {null};
+
+ l = alloc(sizeof(struct block), ATEMP);
+ l->flags = 0;
+ ainit(&l->area); /* todo: could use genv->area (l->area => l->areap) */
+ if (!genv->loc) {
+ l->argc = 0;
+ l->argv = (char **) empty;
+ } else {
+ l->argc = genv->loc->argc;
+ l->argv = genv->loc->argv;
+ }
+ l->exit = l->error = NULL;
+ ktinit(&l->vars, &l->area, 0);
+ ktinit(&l->funs, &l->area, 0);
+ l->next = genv->loc;
+ genv->loc = l;
+}
+
+/*
+ * pop a block handling special variables
+ */
+void
+popblock(void)
+{
+ struct block *l = genv->loc;
+ struct tbl *vp, **vpp = l->vars.tbls, *vq;
+ int i;
+
+ genv->loc = l->next; /* pop block */
+ for (i = l->vars.size; --i >= 0; )
+ if ((vp = *vpp++) != NULL && (vp->flag&SPECIAL)) {
+ if ((vq = global(vp->name))->flag & ISSET)
+ setspec(vq);
+ else
+ unsetspec(vq);
+ }
+ if (l->flags & BF_DOGETOPTS)
+ user_opt = l->getopts_state;
+ afreeall(&l->area);
+ afree(l, ATEMP);
+}
+
+/* called by main() to initialize variable data structures */
+void
+initvar(void)
+{
+ static const struct {
+ const char *name;
+ int v;
+ } names[] = {
+ { "COLUMNS", V_COLUMNS },
+ { "IFS", V_IFS },
+ { "OPTIND", V_OPTIND },
+ { "PATH", V_PATH },
+ { "POSIXLY_CORRECT", V_POSIXLY_CORRECT },
+ { "TMPDIR", V_TMPDIR },
+#ifdef HISTORY
+ { "HISTFILE", V_HISTFILE },
+ { "HISTSIZE", V_HISTSIZE },
+#endif /* HISTORY */
+#ifdef EDIT
+ { "EDITOR", V_EDITOR },
+ { "VISUAL", V_VISUAL },
+#endif /* EDIT */
+ { "MAIL", V_MAIL },
+ { "MAILCHECK", V_MAILCHECK },
+ { "MAILPATH", V_MAILPATH },
+ { "RANDOM", V_RANDOM },
+ { "SECONDS", V_SECONDS },
+ { "TMOUT", V_TMOUT },
+ { "LINENO", V_LINENO },
+ { NULL, 0 }
+ };
+ int i;
+ struct tbl *tp;
+
+ ktinit(&specials, APERM, 32); /* must be 2^n (currently 17 specials) */
+ for (i = 0; names[i].name; i++) {
+ tp = ktenter(&specials, names[i].name, hash(names[i].name));
+ tp->flag = DEFINED|ISSET;
+ tp->type = names[i].v;
+ }
+}
+
+/* Used to calculate an array index for global()/local(). Sets *arrayp to
+ * non-zero if this is an array, sets *valp to the array index, returns
+ * the basename of the array.
+ */
+static const char *
+array_index_calc(const char *n, bool *arrayp, int *valp)
+{
+ const char *p;
+ int len;
+
+ *arrayp = false;
+ p = skip_varname(n, false);
+ if (p != n && *p == '[' && (len = array_ref_len(p))) {
+ char *sub, *tmp;
+ long rval;
+
+ /* Calculate the value of the subscript */
+ *arrayp = true;
+ tmp = str_nsave(p+1, len-2, ATEMP);
+ sub = substitute(tmp, 0);
+ afree(tmp, ATEMP);
+ n = str_nsave(n, p - n, ATEMP);
+ evaluate(sub, &rval, KSH_UNWIND_ERROR, true);
+ if (rval < 0 || rval > INT_MAX)
+ errorf("%s: subscript %ld out of range", n, rval);
+ *valp = rval;
+ afree(sub, ATEMP);
+ }
+ return n;
+}
+
+/*
+ * Search for variable, if not found create globally.
+ */
+struct tbl *
+global(const char *n)
+{
+ struct block *l = genv->loc;
+ struct tbl *vp;
+ long num;
+ int c;
+ unsigned int h;
+ bool array;
+ int val;
+
+ /* Check to see if this is an array */
+ n = array_index_calc(n, &array, &val);
+ h = hash(n);
+ c = (unsigned char)n[0];
+ if (!letter(c)) {
+ if (array)
+ errorf("bad substitution");
+ vp = &vtemp;
+ vp->flag = DEFINED;
+ vp->type = 0;
+ vp->areap = ATEMP;
+ *vp->name = c;
+ if (digit(c)) {
+ errno = 0;
+ num = strtol(n, NULL, 10);
+ if (errno == 0 && num <= l->argc)
+ /* setstr can't fail here */
+ setstr(vp, l->argv[num], KSH_RETURN_ERROR);
+ vp->flag |= RDONLY;
+ return vp;
+ }
+ vp->flag |= RDONLY;
+ if (n[1] != '\0')
+ return vp;
+ vp->flag |= ISSET|INTEGER;
+ switch (c) {
+ case '$':
+ vp->val.i = kshpid;
+ break;
+ case '!':
+ /* If no job, expand to nothing */
+ if ((vp->val.i = j_async()) == 0)
+ vp->flag &= ~(ISSET|INTEGER);
+ break;
+ case '?':
+ vp->val.i = exstat;
+ break;
+ case '#':
+ vp->val.i = l->argc;
+ break;
+ case '-':
+ vp->flag &= ~INTEGER;
+ vp->val.s = getoptions();
+ break;
+ default:
+ vp->flag &= ~(ISSET|INTEGER);
+ }
+ return vp;
+ }
+ for (l = genv->loc; ; l = l->next) {
+ vp = ktsearch(&l->vars, n, h);
+ if (vp != NULL) {
+ if (array)
+ return arraysearch(vp, val);
+ else
+ return vp;
+ }
+ if (l->next == NULL)
+ break;
+ }
+ vp = ktenter(&l->vars, n, h);
+ if (array)
+ vp = arraysearch(vp, val);
+ vp->flag |= DEFINED;
+ if (special(n))
+ vp->flag |= SPECIAL;
+ return vp;
+}
+
+/*
+ * Search for local variable, if not found create locally.
+ */
+struct tbl *
+local(const char *n, bool copy)
+{
+ struct block *l = genv->loc;
+ struct tbl *vp;
+ unsigned int h;
+ bool array;
+ int val;
+
+ /* Check to see if this is an array */
+ n = array_index_calc(n, &array, &val);
+ h = hash(n);
+ if (!letter(*n)) {
+ vp = &vtemp;
+ vp->flag = DEFINED|RDONLY;
+ vp->type = 0;
+ vp->areap = ATEMP;
+ return vp;
+ }
+ vp = ktenter(&l->vars, n, h);
+ if (copy && !(vp->flag & DEFINED)) {
+ struct block *ll = l;
+ struct tbl *vq = NULL;
+
+ while ((ll = ll->next) && !(vq = ktsearch(&ll->vars, n, h)))
+ ;
+ if (vq) {
+ vp->flag |= vq->flag &
+ (EXPORT | INTEGER | RDONLY | LJUST | RJUST |
+ ZEROFIL | LCASEV | UCASEV_AL | INT_U | INT_L);
+ if (vq->flag & INTEGER)
+ vp->type = vq->type;
+ vp->u2.field = vq->u2.field;
+ }
+ }
+ if (array)
+ vp = arraysearch(vp, val);
+ vp->flag |= DEFINED;
+ if (special(n))
+ vp->flag |= SPECIAL;
+ return vp;
+}
+
+/* get variable string value */
+char *
+str_val(struct tbl *vp)
+{
+ char *s;
+
+ if ((vp->flag&SPECIAL))
+ getspec(vp);
+ if (!(vp->flag&ISSET))
+ s = null; /* special to dollar() */
+ else if (!(vp->flag&INTEGER)) /* string source */
+ s = vp->val.s + vp->type;
+ else { /* integer source */
+ /* worst case number length is when base=2, so use BITS(long) */
+ /* minus base # number null */
+ char strbuf[1 + 2 + 1 + BITS(long) + 1];
+ const char *digits = (vp->flag & UCASEV_AL) ?
+ "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" :
+ "0123456789abcdefghijklmnopqrstuvwxyz";
+ unsigned long n;
+ int base;
+
+ s = strbuf + sizeof(strbuf);
+ if (vp->flag & INT_U)
+ n = (unsigned long) vp->val.i;
+ else
+ n = (vp->val.i < 0) ? -vp->val.i : vp->val.i;
+ base = (vp->type == 0) ? 10 : vp->type;
+ if (base < 2 || base > strlen(digits))
+ base = 10;
+
+ *--s = '\0';
+ do {
+ *--s = digits[n % base];
+ n /= base;
+ } while (n != 0);
+ if (base != 10) {
+ *--s = '#';
+ *--s = digits[base % 10];
+ if (base >= 10)
+ *--s = digits[base / 10];
+ }
+ if (!(vp->flag & INT_U) && vp->val.i < 0)
+ *--s = '-';
+ if (vp->flag & (RJUST|LJUST)) /* case already dealt with */
+ s = formatstr(vp, s);
+ else
+ s = str_save(s, ATEMP);
+ }
+ return s;
+}
+
+/* get variable integer value, with error checking */
+long
+intval(struct tbl *vp)
+{
+ long num;
+ int base;
+
+ base = getint(vp, &num, false);
+ if (base == -1)
+ /* XXX check calls - is error here ok by POSIX? */
+ errorf("%s: bad number", str_val(vp));
+ return num;
+}
+
+/* set variable to string value */
+int
+setstr(struct tbl *vq, const char *s, int error_ok)
+{
+ const char *fs = NULL;
+ int no_ro_check = error_ok & 0x4;
+ error_ok &= ~0x4;
+ if ((vq->flag & RDONLY) && !no_ro_check) {
+ warningf(true, "%s: is read only", vq->name);
+ if (!error_ok)
+ errorf(NULL);
+ return 0;
+ }
+ if (!(vq->flag&INTEGER)) { /* string dest */
+ if ((vq->flag&ALLOC)) {
+ /* debugging */
+ if (s >= vq->val.s &&
+ s <= vq->val.s + strlen(vq->val.s))
+ internal_errorf(true,
+ "setstr: %s=%s: assigning to self",
+ vq->name, s);
+ afree(vq->val.s, vq->areap);
+ }
+ vq->flag &= ~(ISSET|ALLOC);
+ vq->type = 0;
+ if (s && (vq->flag & (UCASEV_AL|LCASEV|LJUST|RJUST)))
+ fs = s = formatstr(vq, s);
+ if ((vq->flag&EXPORT))
+ export(vq, s);
+ else {
+ vq->val.s = str_save(s, vq->areap);
+ vq->flag |= ALLOC;
+ }
+ } else { /* integer dest */
+ if (!v_evaluate(vq, s, error_ok, true))
+ return 0;
+ }
+ vq->flag |= ISSET;
+ if ((vq->flag&SPECIAL))
+ setspec(vq);
+ afree((void *)fs, ATEMP);
+ return 1;
+}
+
+/* set variable to integer */
+void
+setint(struct tbl *vq, long int n)
+{
+ if (!(vq->flag&INTEGER)) {
+ struct tbl *vp = &vtemp;
+ vp->flag = (ISSET|INTEGER);
+ vp->type = 0;
+ vp->areap = ATEMP;
+ vp->val.i = n;
+ /* setstr can't fail here */
+ setstr(vq, str_val(vp), KSH_RETURN_ERROR);
+ } else
+ vq->val.i = n;
+ vq->flag |= ISSET;
+ if ((vq->flag&SPECIAL))
+ setspec(vq);
+}
+
+int
+getint(struct tbl *vp, long int *nump, bool arith)
+{
+ char *s;
+ int c;
+ int base, neg;
+ int have_base = 0;
+ long num;
+
+ if (vp->flag&SPECIAL)
+ getspec(vp);
+ /* XXX is it possible for ISSET to be set and val.s to be 0? */
+ if (!(vp->flag&ISSET) || (!(vp->flag&INTEGER) && vp->val.s == NULL))
+ return -1;
+ if (vp->flag&INTEGER) {
+ *nump = vp->val.i;
+ return vp->type;
+ }
+ s = vp->val.s + vp->type;
+ if (s == NULL) /* redundant given initial test */
+ s = null;
+ base = 10;
+ num = 0;
+ neg = 0;
+ if (arith && *s == '0' && *(s+1)) {
+ s++;
+ if (*s == 'x' || *s == 'X') {
+ s++;
+ base = 16;
+ } else if (vp->flag & ZEROFIL) {
+ while (*s == '0')
+ s++;
+ } else
+ base = 8;
+ have_base++;
+ }
+ for (c = (unsigned char)*s++; c ; c = (unsigned char)*s++) {
+ if (c == '-') {
+ neg++;
+ } else if (c == '#') {
+ base = (int) num;
+ if (have_base || base < 2 || base > 36)
+ return -1;
+ num = 0;
+ have_base = 1;
+ } else if (letnum(c)) {
+ if (isdigit(c))
+ c -= '0';
+ else if (islower(c))
+ c -= 'a' - 10; /* todo: assumes ascii */
+ else if (isupper(c))
+ c -= 'A' - 10; /* todo: assumes ascii */
+ else
+ c = -1; /* _: force error */
+ if (c < 0 || c >= base)
+ return -1;
+ num = num * base + c;
+ } else
+ return -1;
+ }
+ if (neg)
+ num = -num;
+ *nump = num;
+ return base;
+}
+
+/* convert variable vq to integer variable, setting its value from vp
+ * (vq and vp may be the same)
+ */
+struct tbl *
+setint_v(struct tbl *vq, struct tbl *vp, bool arith)
+{
+ int base;
+ long num;
+
+ if ((base = getint(vp, &num, arith)) == -1)
+ return NULL;
+ if (!(vq->flag & INTEGER) && (vq->flag & ALLOC)) {
+ vq->flag &= ~ALLOC;
+ afree(vq->val.s, vq->areap);
+ }
+ vq->val.i = num;
+ if (vq->type == 0) /* default base */
+ vq->type = base;
+ vq->flag |= ISSET|INTEGER;
+ if (vq->flag&SPECIAL)
+ setspec(vq);
+ return vq;
+}
+
+static char *
+formatstr(struct tbl *vp, const char *s)
+{
+ int olen, nlen;
+ char *p, *q;
+
+ olen = strlen(s);
+
+ if (vp->flag & (RJUST|LJUST)) {
+ if (!vp->u2.field) /* default field width */
+ vp->u2.field = olen;
+ nlen = vp->u2.field;
+ } else
+ nlen = olen;
+
+ p = alloc(nlen + 1, ATEMP);
+ if (vp->flag & (RJUST|LJUST)) {
+ int slen;
+
+ if (vp->flag & RJUST) {
+ const char *q = s + olen;
+ /* strip trailing spaces (at&t ksh uses q[-1] == ' ') */
+ while (q > s && isspace((unsigned char)q[-1]))
+ --q;
+ slen = q - s;
+ if (slen > vp->u2.field) {
+ s += slen - vp->u2.field;
+ slen = vp->u2.field;
+ }
+ shf_snprintf(p, nlen + 1,
+ ((vp->flag & ZEROFIL) && digit(*s)) ?
+ "%0*s%.*s" : "%*s%.*s",
+ vp->u2.field - slen, null, slen, s);
+ } else {
+ /* strip leading spaces/zeros */
+ while (isspace((unsigned char)*s))
+ s++;
+ if (vp->flag & ZEROFIL)
+ while (*s == '0')
+ s++;
+ shf_snprintf(p, nlen + 1, "%-*.*s",
+ vp->u2.field, vp->u2.field, s);
+ }
+ } else
+ memcpy(p, s, olen + 1);
+
+ if (vp->flag & UCASEV_AL) {
+ for (q = p; *q; q++)
+ if (islower((unsigned char)*q))
+ *q = toupper((unsigned char)*q);
+ } else if (vp->flag & LCASEV) {
+ for (q = p; *q; q++)
+ if (isupper((unsigned char)*q))
+ *q = tolower((unsigned char)*q);
+ }
+
+ return p;
+}
+
+/*
+ * make vp->val.s be "name=value" for quick exporting.
+ */
+static void
+export(struct tbl *vp, const char *val)
+{
+ char *xp;
+ char *op = (vp->flag&ALLOC) ? vp->val.s : NULL;
+ int namelen = strlen(vp->name);
+ int vallen = strlen(val) + 1;
+
+ vp->flag |= ALLOC;
+ xp = alloc(namelen + 1 + vallen, vp->areap);
+ memcpy(vp->val.s = xp, vp->name, namelen);
+ xp += namelen;
+ *xp++ = '=';
+ vp->type = xp - vp->val.s; /* offset to value */
+ memcpy(xp, val, vallen);
+ afree(op, vp->areap);
+}
+
+/*
+ * lookup variable (according to (set&LOCAL)),
+ * set its attributes (INTEGER, RDONLY, EXPORT, TRACE, LJUST, RJUST, ZEROFIL,
+ * LCASEV, UCASEV_AL), and optionally set its value if an assignment.
+ */
+struct tbl *
+typeset(const char *var, int set, int clr, int field, int base)
+{
+ struct tbl *vp;
+ struct tbl *vpbase, *t;
+ char *tvar;
+ const char *val;
+
+ /* check for valid variable name, search for value */
+ val = skip_varname(var, false);
+ if (val == var)
+ return NULL;
+ if (*val == '[') {
+ int len;
+
+ len = array_ref_len(val);
+ if (len == 0)
+ return NULL;
+ /* IMPORT is only used when the shell starts up and is
+ * setting up its environment. Allow only simple array
+ * references at this time since parameter/command substitution
+ * is preformed on the [expression], which would be a major
+ * security hole.
+ */
+ if (set & IMPORT) {
+ int i;
+ for (i = 1; i < len - 1; i++)
+ if (!digit(val[i]))
+ return NULL;
+ }
+ val += len;
+ }
+ if (*val == '=')
+ tvar = str_nsave(var, val++ - var, ATEMP);
+ else {
+ /* Importing from original environment: must have an = */
+ if (set & IMPORT)
+ return NULL;
+ tvar = (char *) var;
+ val = NULL;
+ }
+
+ /* Prevent typeset from creating a local PATH/ENV/SHELL */
+ if (Flag(FRESTRICTED) && (strcmp(tvar, "PATH") == 0 ||
+ strcmp(tvar, "ENV") == 0 || strcmp(tvar, "SHELL") == 0))
+ errorf("%s: restricted", tvar);
+
+ vp = (set&LOCAL) ? local(tvar, (set & LOCAL_COPY) ? true : false) :
+ global(tvar);
+ set &= ~(LOCAL|LOCAL_COPY);
+
+ vpbase = (vp->flag & ARRAY) ? global(arrayname(var)) : vp;
+
+ /* only allow export flag to be set. at&t ksh allows any attribute to
+ * be changed, which means it can be truncated or modified
+ * (-L/-R/-Z/-i).
+ */
+ if ((vpbase->flag&RDONLY) &&
+ (val || clr || (set & ~EXPORT)))
+ /* XXX check calls - is error here ok by POSIX? */
+ errorf("%s: is read only", tvar);
+ if (val)
+ afree(tvar, ATEMP);
+
+ /* most calls are with set/clr == 0 */
+ if (set | clr) {
+ int ok = 1;
+ /* XXX if x[0] isn't set, there will be problems: need to have
+ * one copy of attributes for arrays...
+ */
+ for (t = vpbase; t; t = t->u.array) {
+ int fake_assign;
+ char *s = NULL;
+ char *free_me = NULL;
+
+ fake_assign = (t->flag & ISSET) && (!val || t != vp) &&
+ ((set & (UCASEV_AL|LCASEV|LJUST|RJUST|ZEROFIL)) ||
+ ((t->flag & INTEGER) && (clr & INTEGER)) ||
+ (!(t->flag & INTEGER) && (set & INTEGER)));
+ if (fake_assign) {
+ if (t->flag & INTEGER) {
+ s = str_val(t);
+ free_me = NULL;
+ } else {
+ s = t->val.s + t->type;
+ free_me = (t->flag & ALLOC) ? t->val.s :
+ NULL;
+ }
+ t->flag &= ~ALLOC;
+ }
+ if (!(t->flag & INTEGER) && (set & INTEGER)) {
+ t->type = 0;
+ t->flag &= ~ALLOC;
+ }
+ t->flag = (t->flag | set) & ~clr;
+ /* Don't change base if assignment is to be done,
+ * in case assignment fails.
+ */
+ if ((set & INTEGER) && base > 0 && (!val || t != vp))
+ t->type = base;
+ if (set & (LJUST|RJUST|ZEROFIL))
+ t->u2.field = field;
+ if (fake_assign) {
+ if (!setstr(t, s, KSH_RETURN_ERROR)) {
+ /* Somewhat arbitrary action here:
+ * zap contents of variable, but keep
+ * the flag settings.
+ */
+ ok = 0;
+ if (t->flag & INTEGER)
+ t->flag &= ~ISSET;
+ else {
+ if (t->flag & ALLOC)
+ afree(t->val.s, t->areap);
+ t->flag &= ~(ISSET|ALLOC);
+ t->type = 0;
+ }
+ }
+ afree(free_me, t->areap);
+ }
+ }
+ if (!ok)
+ errorf(NULL);
+ }
+
+ if (val != NULL) {
+ if (vp->flag&INTEGER) {
+ /* do not zero base before assignment */
+ setstr(vp, val, KSH_UNWIND_ERROR | 0x4);
+ /* Done after assignment to override default */
+ if (base > 0)
+ vp->type = base;
+ } else
+ /* setstr can't fail (readonly check already done) */
+ setstr(vp, val, KSH_RETURN_ERROR | 0x4);
+ }
+
+ /* only x[0] is ever exported, so use vpbase */
+ if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER) &&
+ vpbase->type == 0)
+ export(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null);
+
+ return vp;
+}
+
+/* Unset a variable. array_ref is set if there was an array reference in
+ * the name lookup (eg, x[2]).
+ */
+void
+unset(struct tbl *vp, int array_ref)
+{
+ if (vp->flag & ALLOC)
+ afree(vp->val.s, vp->areap);
+ if ((vp->flag & ARRAY) && !array_ref) {
+ struct tbl *a, *tmp;
+
+ /* Free up entire array */
+ for (a = vp->u.array; a; ) {
+ tmp = a;
+ a = a->u.array;
+ if (tmp->flag & ALLOC)
+ afree(tmp->val.s, tmp->areap);
+ afree(tmp, tmp->areap);
+ }
+ vp->u.array = NULL;
+ }
+ /* If foo[0] is being unset, the remainder of the array is kept... */
+ vp->flag &= SPECIAL | (array_ref ? ARRAY|DEFINED : 0);
+ if (vp->flag & SPECIAL)
+ unsetspec(vp); /* responsible for `unspecial'ing var */
+}
+
+/* return a pointer to the first char past a legal variable name (returns the
+ * argument if there is no legal name, returns * a pointer to the terminating
+ * null if whole string is legal).
+ */
+char *
+skip_varname(const char *s, int aok)
+{
+ int alen;
+
+ if (s && letter(*s)) {
+ while (*++s && letnum(*s))
+ ;
+ if (aok && *s == '[' && (alen = array_ref_len(s)))
+ s += alen;
+ }
+ return (char *) s;
+}
+
+/* Return a pointer to the first character past any legal variable name. */
+char *
+skip_wdvarname(const char *s,
+ int aok) /* skip array de-reference? */
+{
+ if (s[0] == CHAR && letter(s[1])) {
+ do {
+ s += 2;
+ } while (s[0] == CHAR && letnum(s[1]));
+ if (aok && s[0] == CHAR && s[1] == '[') {
+ /* skip possible array de-reference */
+ const char *p = s;
+ char c;
+ int depth = 0;
+
+ while (1) {
+ if (p[0] != CHAR)
+ break;
+ c = p[1];
+ p += 2;
+ if (c == '[')
+ depth++;
+ else if (c == ']' && --depth == 0) {
+ s = p;
+ break;
+ }
+ }
+ }
+ }
+ return (char *) s;
+}
+
+/* Check if coded string s is a variable name */
+int
+is_wdvarname(const char *s, int aok)
+{
+ char *p = skip_wdvarname(s, aok);
+
+ return p != s && p[0] == EOS;
+}
+
+/* Check if coded string s is a variable assignment */
+int
+is_wdvarassign(const char *s)
+{
+ char *p = skip_wdvarname(s, true);
+
+ return p != s && p[0] == CHAR && p[1] == '=';
+}
+
+/*
+ * Make the exported environment from the exported names in the dictionary.
+ */
+char **
+makenv(void)
+{
+ struct block *l;
+ XPtrV env;
+ struct tbl *vp, **vpp;
+ int i;
+
+ XPinit(env, 64);
+ for (l = genv->loc; l != NULL; l = l->next)
+ for (vpp = l->vars.tbls, i = l->vars.size; --i >= 0; )
+ if ((vp = *vpp++) != NULL &&
+ (vp->flag&(ISSET|EXPORT)) == (ISSET|EXPORT)) {
+ struct block *l2;
+ struct tbl *vp2;
+ unsigned int h = hash(vp->name);
+
+ /* unexport any redefined instances */
+ for (l2 = l->next; l2 != NULL; l2 = l2->next) {
+ vp2 = ktsearch(&l2->vars, vp->name, h);
+ if (vp2 != NULL)
+ vp2->flag &= ~EXPORT;
+ }
+ if ((vp->flag&INTEGER)) {
+ /* integer to string */
+ char *val;
+ val = str_val(vp);
+ vp->flag &= ~(INTEGER|RDONLY);
+ /* setstr can't fail here */
+ setstr(vp, val, KSH_RETURN_ERROR);
+ }
+ XPput(env, vp->val.s);
+ }
+ XPput(env, NULL);
+ return (char **) XPclose(env);
+}
+
+/*
+ * Called after a fork in parent to bump the random number generator.
+ * Done to ensure children will not get the same random number sequence
+ * if the parent doesn't use $RANDOM.
+ */
+void
+change_random(void)
+{
+ rand();
+}
+
+/*
+ * handle special variables with side effects - PATH, SECONDS.
+ */
+
+/* Test if name is a special parameter */
+static int
+special(const char *name)
+{
+ struct tbl *tp;
+
+ tp = ktsearch(&specials, name, hash(name));
+ return tp && (tp->flag & ISSET) ? tp->type : V_NONE;
+}
+
+/* Make a variable non-special */
+static void
+unspecial(const char *name)
+{
+ struct tbl *tp;
+
+ tp = ktsearch(&specials, name, hash(name));
+ if (tp)
+ ktdelete(tp);
+}
+
+static time_t seconds; /* time SECONDS last set */
+static int user_lineno; /* what user set $LINENO to */
+
+static void
+getspec(struct tbl *vp)
+{
+ switch (special(vp->name)) {
+ case V_SECONDS:
+ vp->flag &= ~SPECIAL;
+ /* On start up the value of SECONDS is used before seconds
+ * has been set - don't do anything in this case
+ * (see initcoms[] in main.c).
+ */
+ if (vp->flag & ISSET)
+ setint(vp, (long)(time(NULL) - seconds)); /* XXX 2038 */
+ vp->flag |= SPECIAL;
+ break;
+ case V_RANDOM:
+ vp->flag &= ~SPECIAL;
+ setint(vp, (long) (rand() & 0x7fff));
+ vp->flag |= SPECIAL;
+ break;
+#ifdef HISTORY
+ case V_HISTSIZE:
+ vp->flag &= ~SPECIAL;
+ setint(vp, (long) histsize);
+ vp->flag |= SPECIAL;
+ break;
+#endif /* HISTORY */
+ case V_OPTIND:
+ vp->flag &= ~SPECIAL;
+ setint(vp, (long) user_opt.uoptind);
+ vp->flag |= SPECIAL;
+ break;
+ case V_LINENO:
+ vp->flag &= ~SPECIAL;
+ setint(vp, (long) current_lineno + user_lineno);
+ vp->flag |= SPECIAL;
+ break;
+ }
+}
+
+static void
+setspec(struct tbl *vp)
+{
+ char *s;
+
+ switch (special(vp->name)) {
+ case V_PATH:
+ afree(path, APERM);
+ path = str_save(str_val(vp), APERM);
+ flushcom(1); /* clear tracked aliases */
+ break;
+ case V_IFS:
+ setctypes(s = str_val(vp), C_IFS);
+ ifs0 = *s;
+ break;
+ case V_OPTIND:
+ vp->flag &= ~SPECIAL;
+ getopts_reset((int) intval(vp));
+ vp->flag |= SPECIAL;
+ break;
+ case V_POSIXLY_CORRECT:
+ change_flag(FPOSIX, OF_SPECIAL, 1);
+ break;
+ case V_TMPDIR:
+ if (tmpdir) {
+ afree(tmpdir, APERM);
+ tmpdir = NULL;
+ }
+ /* Use tmpdir iff it is an absolute path, is writable and
+ * searchable and is a directory...
+ */
+ {
+ struct stat statb;
+
+ s = str_val(vp);
+ if (s[0] == '/' && access(s, W_OK|X_OK) == 0 &&
+ stat(s, &statb) == 0 && S_ISDIR(statb.st_mode))
+ tmpdir = str_save(s, APERM);
+ }
+ break;
+#ifdef HISTORY
+ case V_HISTSIZE:
+ vp->flag &= ~SPECIAL;
+ sethistsize((int) intval(vp));
+ vp->flag |= SPECIAL;
+ break;
+ case V_HISTFILE:
+ sethistfile(str_val(vp));
+ break;
+#endif /* HISTORY */
+#ifdef EDIT
+ case V_VISUAL:
+ set_editmode(str_val(vp));
+ break;
+ case V_EDITOR:
+ if (!(global("VISUAL")->flag & ISSET))
+ set_editmode(str_val(vp));
+ break;
+ case V_COLUMNS:
+ {
+ long l;
+
+ if (getint(vp, &l, false) == -1) {
+ x_cols = MIN_COLS;
+ break;
+ }
+ if (l <= MIN_COLS || l > INT_MAX)
+ x_cols = MIN_COLS;
+ else
+ x_cols = l;
+ }
+ break;
+#endif /* EDIT */
+ case V_MAIL:
+ mbset(str_val(vp));
+ break;
+ case V_MAILPATH:
+ mpset(str_val(vp));
+ break;
+ case V_MAILCHECK:
+ vp->flag &= ~SPECIAL;
+ mcset(intval(vp));
+ vp->flag |= SPECIAL;
+ break;
+ case V_RANDOM:
+ vp->flag &= ~SPECIAL;
+ srand_deterministic((unsigned int)intval(vp));
+ vp->flag |= SPECIAL;
+ break;
+ case V_SECONDS:
+ vp->flag &= ~SPECIAL;
+ seconds = time(NULL) - intval(vp); /* XXX 2038 */
+ vp->flag |= SPECIAL;
+ break;
+ case V_TMOUT:
+ /* at&t ksh seems to do this (only listen if integer) */
+ if (vp->flag & INTEGER)
+ ksh_tmout = vp->val.i >= 0 ? vp->val.i : 0;
+ break;
+ case V_LINENO:
+ vp->flag &= ~SPECIAL;
+ /* The -1 is because line numbering starts at 1. */
+ user_lineno = (unsigned int) intval(vp) - current_lineno - 1;
+ vp->flag |= SPECIAL;
+ break;
+ }
+}
+
+static void
+unsetspec(struct tbl *vp)
+{
+ switch (special(vp->name)) {
+ case V_PATH:
+ afree(path, APERM);
+ path = str_save(def_path, APERM);
+ flushcom(1); /* clear tracked aliases */
+ break;
+ case V_IFS:
+ setctypes(" \t\n", C_IFS);
+ ifs0 = ' ';
+ break;
+ case V_TMPDIR:
+ /* should not become unspecial */
+ if (tmpdir) {
+ afree(tmpdir, APERM);
+ tmpdir = NULL;
+ }
+ break;
+ case V_MAIL:
+ mbset(NULL);
+ break;
+ case V_MAILPATH:
+ mpset(NULL);
+ break;
+ case V_LINENO:
+ case V_MAILCHECK: /* at&t ksh leaves previous value in place */
+ case V_RANDOM:
+ case V_SECONDS:
+ case V_TMOUT: /* at&t ksh leaves previous value in place */
+ unspecial(vp->name);
+ break;
+
+ /* at&t ksh man page says OPTIND, OPTARG and _ lose special meaning,
+ * but OPTARG does not (still set by getopts) and _ is also still
+ * set in various places.
+ * Don't know what at&t does for:
+ * MAIL, MAILPATH, HISTSIZE, HISTFILE,
+ * Unsetting these in at&t ksh does not loose the `specialness':
+ * no effect: IFS, COLUMNS, PATH, TMPDIR,
+ * VISUAL, EDITOR,
+ * pdkshisms: no effect:
+ * POSIXLY_CORRECT (use set +o posix instead)
+ */
+ }
+}
+
+/*
+ * Search for (and possibly create) a table entry starting with
+ * vp, indexed by val.
+ */
+static struct tbl *
+arraysearch(struct tbl *vp, int val)
+{
+ struct tbl *prev, *curr, *new;
+ size_t namelen = strlen(vp->name) + 1;
+
+ vp->flag |= ARRAY|DEFINED;
+ vp->index = 0;
+ /* The table entry is always [0] */
+ if (val == 0)
+ return vp;
+ prev = vp;
+ curr = vp->u.array;
+ while (curr && curr->index < val) {
+ prev = curr;
+ curr = curr->u.array;
+ }
+ if (curr && curr->index == val) {
+ if (curr->flag&ISSET)
+ return curr;
+ else
+ new = curr;
+ } else
+ new = alloc(sizeof(struct tbl) + namelen,
+ vp->areap);
+ strlcpy(new->name, vp->name, namelen);
+ new->flag = vp->flag & ~(ALLOC|DEFINED|ISSET|SPECIAL);
+ new->type = vp->type;
+ new->areap = vp->areap;
+ new->u2.field = vp->u2.field;
+ new->index = val;
+ if (curr != new) { /* not reusing old array entry */
+ prev->u.array = new;
+ new->u.array = curr;
+ }
+ return new;
+}
+
+/* Return the length of an array reference (eg, [1+2]) - cp is assumed
+ * to point to the open bracket. Returns 0 if there is no matching closing
+ * bracket.
+ */
+int
+array_ref_len(const char *cp)
+{
+ const char *s = cp;
+ int c;
+ int depth = 0;
+
+ while ((c = *s++) && (c != ']' || --depth))
+ if (c == '[')
+ depth++;
+ if (!c)
+ return 0;
+ return s - cp;
+}
+
+/*
+ * Make a copy of the base of an array name
+ */
+char *
+arrayname(const char *str)
+{
+ const char *p;
+
+ if ((p = strchr(str, '[')) == 0)
+ /* Shouldn't happen, but why worry? */
+ return (char *) str;
+
+ return str_nsave(str, p - str, ATEMP);
+}
+
+/* Set (or overwrite, if !reset) the array variable var to the values in vals.
+ */
+void
+set_array(const char *var, int reset, char **vals)
+{
+ struct tbl *vp, *vq;
+ int i;
+
+ /* to get local array, use "typeset foo; set -A foo" */
+ vp = global(var);
+
+ /* Note: at&t ksh allows set -A but not set +A of a read-only var */
+ if ((vp->flag&RDONLY))
+ errorf("%s: is read only", var);
+ /* This code is quite non-optimal */
+ if (reset > 0)
+ /* trash existing values and attributes */
+ unset(vp, 0);
+ /* todo: would be nice for assignment to completely succeed or
+ * completely fail. Only really effects integer arrays:
+ * evaluation of some of vals[] may fail...
+ */
+ for (i = 0; vals[i]; i++) {
+ vq = arraysearch(vp, i);
+ /* would be nice to deal with errors here... (see above) */
+ setstr(vq, vals[i], KSH_RETURN_ERROR);
+ }
+}