/* $OpenBSD: var.c,v 1.44 2015/09/10 11:37:42 jca Exp $ */ /*- * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, * 2011, 2012, 2013, 2014, 2015, 2016 * mirabilos * * Provided that these terms and disclaimer and all copyright notices * are retained or reproduced in an accompanying document, permission * is granted to deal in this work without restriction, including un- * limited rights to use, publicly perform, distribute, sell, modify, * merge, give away, or sublicence. * * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to * the utmost extent permitted by applicable law, neither express nor * implied; without malicious intent or gross negligence. In no event * may a licensor, author or contributor be held liable for indirect, * direct, other damage, loss, or other issues arising in any way out * of dealing in the work, even if advised of the possibility of such * damage or existence of a defect, except proven that it results out * of said person's immediate fault when using the work as intended. */ #include "sh.h" #include "mirhash.h" #if defined(__OpenBSD__) #include #endif __RCSID("$MirOS: src/bin/mksh/var.c,v 1.196 2016/01/14 20:21:39 tg Exp $"); /*- * 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 table specials; static uint32_t lcg_state = 5381, qh_state = 4711; /* may only be set by typeset() just before call to array_index_calc() */ static enum namerefflag innermost_refflag = SRF_NOP; static char *formatstr(struct tbl *, const char *); static void exportprep(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 int getint(struct tbl *, mksh_ari_u *, bool); static const char *array_index_calc(const char *, bool *, uint32_t *); /* * create a new block for function calls and simple commands * assume caller has allocated and set up e->loc */ void newblock(void) { struct block *l; static const char *empty[] = { null }; l = alloc(sizeof(struct block), ATEMP); l->flags = 0; /* TODO: could use e->area (l->area => l->areap) */ ainit(&l->area); if (!e->loc) { l->argc = 0; l->argv = empty; } else { l->argc = e->loc->argc; l->argv = e->loc->argv; } l->exit = l->error = NULL; ktinit(&l->area, &l->vars, 0); ktinit(&l->area, &l->funs, 0); l->next = e->loc; e->loc = l; } /* * pop a block handling special variables */ void popblock(void) { ssize_t i; struct block *l = e->loc; struct tbl *vp, **vpp = l->vars.tbls, *vq; /* pop block */ e->loc = l->next; i = 1 << (l->vars.tshift); while (--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 initialise variable data structures */ #define VARSPEC_DEFNS #include "var_spec.h" enum var_specs { #define VARSPEC_ENUMS #include "var_spec.h" V_MAX }; /* this is biased with -1 relative to VARSPEC_ENUMS */ static const char * const initvar_names[] = { #define VARSPEC_ITEMS #include "var_spec.h" }; void initvar(void) { int i = 0; struct tbl *tp; ktinit(APERM, &specials, /* currently 14 specials: 75% of 32 = 2^5 */ 5); while (i < V_MAX - 1) { tp = ktenter(&specials, initvar_names[i], hash(initvar_names[i])); tp->flag = DEFINED|ISSET; tp->type = ++i; } } /* common code for several functions below and c_typeset() */ struct block * varsearch(struct block *l, struct tbl **vpp, const char *vn, uint32_t h) { register struct tbl *vp; if (l) { varsearch_loop: if ((vp = ktsearch(&l->vars, vn, h)) != NULL) goto varsearch_out; if (l->next != NULL) { l = l->next; goto varsearch_loop; } } vp = NULL; varsearch_out: *vpp = vp; return (l); } /* * Used to calculate an array index for global()/local(). Sets *arrayp * to true if this is an array, sets *valp to the array index, returns * the basename of the array. May only be called from global()/local() * and must be their first callee. */ static const char * array_index_calc(const char *n, bool *arrayp, uint32_t *valp) { const char *p; size_t len; char *ap = NULL; *arrayp = false; redo_from_ref: p = skip_varname(n, false); if (innermost_refflag == SRF_NOP && (p != n) && ksh_isalphx(n[0])) { struct tbl *vp; char *vn; strndupx(vn, n, p - n, ATEMP); /* check if this is a reference */ varsearch(e->loc, &vp, vn, hash(vn)); afree(vn, ATEMP); if (vp && (vp->flag & (DEFINED | ASSOC | ARRAY)) == (DEFINED | ASSOC)) { char *cp; /* gotcha! */ cp = shf_smprintf("%s%s", str_val(vp), p); afree(ap, ATEMP); n = ap = cp; goto redo_from_ref; } } innermost_refflag = SRF_NOP; if (p != n && *p == '[' && (len = array_ref_len(p))) { char *sub, *tmp; mksh_ari_t rval; /* calculate the value of the subscript */ *arrayp = true; strndupx(tmp, p + 1, len - 2, ATEMP); sub = substitute(tmp, 0); afree(tmp, ATEMP); strndupx(n, n, p - n, ATEMP); evaluate(sub, &rval, KSH_UNWIND_ERROR, true); *valp = (uint32_t)rval; afree(sub, ATEMP); } return (n); } #define vn vname.ro /* * Search for variable, if not found create globally. */ struct tbl * global(const char *n) { struct tbl *vp; union mksh_cchack vname; struct block *l = e->loc; int c; bool array; uint32_t h, val; /* * check to see if this is an array; * dereference namerefs; must come first */ vn = array_index_calc(n, &array, &val); h = hash(vn); c = (unsigned char)vn[0]; if (!ksh_isalphx(c)) { if (array) errorf("bad substitution"); vp = &vtemp; vp->flag = DEFINED; vp->type = 0; vp->areap = ATEMP; *vp->name = c; if (ksh_isdigit(c)) { if (getn(vn, &c) && (c <= l->argc)) /* setstr can't fail here */ setstr(vp, l->argv[c], KSH_RETURN_ERROR); vp->flag |= RDONLY; goto out; } vp->flag |= RDONLY; if (vn[1] != '\0') goto out; 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 & 0xFF; break; case '#': vp->val.i = l->argc; break; case '-': vp->flag &= ~INTEGER; vp->val.s = getoptions(); break; default: vp->flag &= ~(ISSET|INTEGER); } goto out; } l = varsearch(e->loc, &vp, vn, h); if (vp != NULL) { if (array) vp = arraysearch(vp, val); goto out; } vp = ktenter(&l->vars, vn, h); if (array) vp = arraysearch(vp, val); vp->flag |= DEFINED; if (special(vn)) vp->flag |= SPECIAL; out: if (vn != n) afree(vname.rw, ATEMP); return (vp); } /* * Search for local variable, if not found create locally. */ struct tbl * local(const char *n, bool copy) { struct tbl *vp; union mksh_cchack vname; struct block *l = e->loc; bool array; uint32_t h, val; /* * check to see if this is an array; * dereference namerefs; must come first */ vn = array_index_calc(n, &array, &val); h = hash(vn); if (!ksh_isalphx(*vn)) { vp = &vtemp; vp->flag = DEFINED|RDONLY; vp->type = 0; vp->areap = ATEMP; goto out; } vp = ktenter(&l->vars, vn, h); if (copy && !(vp->flag & DEFINED)) { struct tbl *vq; varsearch(l->next, &vq, vn, h); if (vq != NULL) { 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(vn)) vp->flag |= SPECIAL; out: if (vn != n) afree(vname.rw, ATEMP); return (vp); } #undef vn /* get variable string value */ char * str_val(struct tbl *vp) { char *s; if ((vp->flag&SPECIAL)) getspec(vp); if (!(vp->flag&ISSET)) /* special to dollar() */ s = null; else if (!(vp->flag&INTEGER)) /* string source */ s = vp->val.s + vp->type; else { /* integer source */ mksh_uari_t n; unsigned int base; /** * worst case number length is when base == 2: * 1 (minus) + 2 (base, up to 36) + 1 ('#') + * number of bits in the mksh_uari_t + 1 (NUL) */ char strbuf[1 + 2 + 1 + 8 * sizeof(mksh_uari_t) + 1]; const char *digits = (vp->flag & UCASEV_AL) ? digits_uc : digits_lc; s = strbuf + sizeof(strbuf); if (vp->flag & INT_U) n = vp->val.u; else n = (vp->val.i < 0) ? -vp->val.u : vp->val.u; base = (vp->type == 0) ? 10U : (unsigned int)vp->type; if (base == 1 && n == 0) base = 2; if (base == 1) { size_t sz = 1; *(s = strbuf) = '1'; s[1] = '#'; if (!UTFMODE || ((n & 0xFF80) == 0xEF80)) /* OPTU-16 -> raw octet */ s[2] = n & 0xFF; else sz = utf_wctomb(s + 2, n); s[2 + sz] = '\0'; } else { *--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 strdupx(s, s, ATEMP); } return (s); } /* set variable to string value */ int setstr(struct tbl *vq, const char *s, int error_ok) { char *salloc = NULL; bool no_ro_check = tobool(error_ok & 0x4); error_ok &= ~0x4; if ((vq->flag & RDONLY) && !no_ro_check) { warningf(true, "read-only: %s", vq->name); if (!error_ok) errorfxz(2); return (0); } if (!(vq->flag&INTEGER)) { /* string dest */ if ((vq->flag&ALLOC)) { #ifndef MKSH_SMALL /* debugging */ if (s >= vq->val.s && s <= vq->val.s + strlen(vq->val.s)) { internal_errorf( "setstr: %s=%s: assigning to self", vq->name, s); } #endif afree(vq->val.s, vq->areap); } vq->flag &= ~(ISSET|ALLOC); vq->type = 0; if (s && (vq->flag & (UCASEV_AL|LCASEV|LJUST|RJUST))) s = salloc = formatstr(vq, s); if ((vq->flag&EXPORT)) exportprep(vq, s); else { strdupx(vq->val.s, 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(salloc, ATEMP); return (1); } /* set variable to integer */ void setint(struct tbl *vq, mksh_ari_t 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); } static int getint(struct tbl *vp, mksh_ari_u *nump, bool arith) { mksh_uari_t c, num = 0, base = 10; const char *s; bool have_base = false, neg = false; if (vp->flag & SPECIAL) getspec(vp); /* XXX is it possible for ISSET to be set and val.s to be NULL? */ if (!(vp->flag & ISSET) || (!(vp->flag & INTEGER) && vp->val.s == NULL)) return (-1); if (vp->flag & INTEGER) { nump->i = vp->val.i; return (vp->type); } s = vp->val.s + vp->type; do { c = (unsigned char)*s++; } while (ksh_isspace(c)); switch (c) { case '-': neg = true; /* FALLTHROUGH */ case '+': c = (unsigned char)*s++; break; } if (c == '0' && arith) { if (ksh_eq(s[0], 'X', 'x')) { /* interpret as hexadecimal */ base = 16; ++s; goto getint_c_style_base; } else if (Flag(FPOSIX) && ksh_isdigit(s[0]) && !(vp->flag & ZEROFIL)) { /* interpret as octal (deprecated) */ base = 8; getint_c_style_base: have_base = true; c = (unsigned char)*s++; } } do { if (c == '#') { /* ksh-style base determination */ if (have_base || num < 1) return (-1); if ((base = num) == 1) { /* mksh-specific extension */ unsigned int wc; if (!UTFMODE) wc = *(const unsigned char *)s; else if (utf_mbtowc(&wc, s) == (size_t)-1) /* OPTU-8 -> OPTU-16 */ /* * (with a twist: 1#\uEF80 converts * the same as 1#\x80 does, thus is * not round-tripping correctly XXX) */ wc = 0xEF00 + *(const unsigned char *)s; nump->u = (mksh_uari_t)wc; return (1); } else if (base > 36) base = 10; num = 0; have_base = true; continue; } if (ksh_isdigit(c)) c = ksh_numdig(c); else if (ksh_isupper(c)) c = ksh_numuc(c) + 10; else if (ksh_islower(c)) c = ksh_numlc(c) + 10; else return (-1); if (c >= base) return (-1); /* handle overflow as truncation */ num = num * base + c; } while ((c = (unsigned char)*s++)); if (neg) num = -num; nump->u = 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; mksh_ari_u num; if ((base = getint(vp, &num, arith)) == -1) return (NULL); setint_n(vq, num.i, 0); if (vq->type == 0) /* default base */ vq->type = base; return (vq); } /* convert variable vq to integer variable, setting its value to num */ void setint_n(struct tbl *vq, mksh_ari_t num, int newbase) { if (!(vq->flag & INTEGER) && (vq->flag & ALLOC)) { vq->flag &= ~ALLOC; vq->type = 0; afree(vq->val.s, vq->areap); } vq->val.i = num; if (newbase != 0) vq->type = newbase; vq->flag |= ISSET|INTEGER; if (vq->flag&SPECIAL) setspec(vq); } static char * formatstr(struct tbl *vp, const char *s) { int olen, nlen; char *p, *q; size_t psiz; olen = (int)utf_mbswidth(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((psiz = nlen * /* MB_LEN_MAX */ 3 + 1), ATEMP); if (vp->flag & (RJUST|LJUST)) { int slen = olen, i = 0; if (vp->flag & RJUST) { const char *qq = s; int n = 0; while (i < slen) i += utf_widthadj(qq, &qq); /* strip trailing spaces (AT&T uses qq[-1] == ' ') */ while (qq > s && ksh_isspace(qq[-1])) { --qq; --slen; } if (vp->flag & ZEROFIL && vp->flag & INTEGER) { if (!s[0] || !s[1]) goto uhm_no; if (s[1] == '#') n = 2; else if (s[2] == '#') n = 3; uhm_no: if (vp->u2.field <= n) n = 0; } if (n) { memcpy(p, s, n); s += n; } while (slen > vp->u2.field) slen -= utf_widthadj(s, &s); if (vp->u2.field - slen) memset(p + n, (vp->flag & ZEROFIL) ? '0' : ' ', vp->u2.field - slen); slen -= n; shf_snprintf(p + vp->u2.field - slen, psiz - (vp->u2.field - slen), "%.*s", slen, s); } else { /* strip leading spaces/zeros */ while (ksh_isspace(*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, strlen(s) + 1); if (vp->flag & UCASEV_AL) { for (q = p; *q; q++) *q = ksh_toupper(*q); } else if (vp->flag & LCASEV) { for (q = p; *q; q++) *q = ksh_tolower(*q); } return (p); } /* * make vp->val.s be "name=value" for quick exporting. */ static void exportprep(struct tbl *vp, const char *val) { char *xp; char *op = (vp->flag&ALLOC) ? vp->val.s : NULL; size_t namelen, vallen; namelen = strlen(vp->name); vallen = strlen(val) + 1; vp->flag |= ALLOC; /* since name+val are both in memory this can go unchecked */ xp = alloc(namelen + 1 + vallen, vp->areap); memcpy(vp->val.s = xp, vp->name, namelen); xp += namelen; *xp++ = '='; /* offset to value */ vp->type = xp - vp->val.s; 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, uint32_t set, uint32_t clr, int field, int base) { struct tbl *vp; struct tbl *vpbase, *t; char *tvar; const char *val; size_t len; bool vappend = false; enum namerefflag new_refflag = SRF_NOP; if ((set & (ARRAY | ASSOC)) == ASSOC) { new_refflag = SRF_ENABLE; set &= ~(ARRAY | ASSOC); } if ((clr & (ARRAY | ASSOC)) == ASSOC) { new_refflag = SRF_DISABLE; clr &= ~(ARRAY | ASSOC); } /* check for valid variable name, search for value */ val = skip_varname(var, false); if (val == var) { /* no variable name given */ return (NULL); } if (*val == '[') { if (new_refflag != SRF_NOP) errorf("%s: %s", var, "reference variable can't be an array"); 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 performed on the [expression] which * would be a major security hole. */ if (set & IMPORT) { size_t i; for (i = 1; i < len - 1; i++) if (!ksh_isdigit(val[i])) return (NULL); } val += len; } if (val[0] == '=') { strndupx(tvar, var, val - var, ATEMP); ++val; } else if (set & IMPORT) { /* environment invalid variable name or no assignment */ return (NULL); } else if (val[0] == '+' && val[1] == '=') { strndupx(tvar, var, val - var, ATEMP); val += 2; vappend = true; } else if (val[0] != '\0') { /* other invalid variable names (not from environment) */ return (NULL); } else { /* just varname with no value part nor equals sign */ strdupx(tvar, var, ATEMP); val = NULL; /* handle foo[*] => foo (whole array) mapping for R39b */ len = strlen(tvar); if (len > 3 && tvar[len - 3] == '[' && tvar[len - 2] == '*' && tvar[len - 1] == ']') tvar[len - 3] = '\0'; } if (new_refflag == SRF_ENABLE) { const char *qval, *ccp; /* bail out on 'nameref foo+=bar' */ if (vappend) errorf("appending not allowed for nameref"); /* find value if variable already exists */ if ((qval = val) == NULL) { varsearch(e->loc, &vp, tvar, hash(tvar)); if (vp == NULL) goto nameref_empty; qval = str_val(vp); } /* check target value for being a valid variable name */ ccp = skip_varname(qval, false); if (ccp == qval) { if (ksh_isdigit(qval[0])) { int c; if (getn(qval, &c)) goto nameref_rhs_checked; } else if (qval[1] == '\0') switch (qval[0]) { case '$': case '!': case '?': case '#': case '-': goto nameref_rhs_checked; } nameref_empty: errorf("%s: %s", var, "empty nameref target"); } len = (*ccp == '[') ? array_ref_len(ccp) : 0; if (ccp[len]) { /* * works for cases "no array", "valid array with * junk after it" and "invalid array"; in the * latter case, len is also 0 and points to '[' */ errorf("%s: %s", qval, "nameref target not a valid parameter name"); } nameref_rhs_checked: /* prevent nameref loops */ while (qval) { if (!strcmp(qval, tvar)) errorf("%s: %s", qval, "expression recurses on parameter"); varsearch(e->loc, &vp, qval, hash(qval)); qval = NULL; if (vp && ((vp->flag & (ARRAY | ASSOC)) == ASSOC)) qval = str_val(vp); } } /* 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: %s", tvar, "restricted"); innermost_refflag = new_refflag; vp = (set & LOCAL) ? local(tvar, tobool(set & LOCAL_COPY)) : global(tvar); if (new_refflag == SRF_DISABLE && (vp->flag & (ARRAY|ASSOC)) == ASSOC) vp->flag &= ~ASSOC; else if (new_refflag == SRF_ENABLE) { if (vp->flag & ARRAY) { 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; vp->flag &= ~ARRAY; } vp->flag |= ASSOC; } set &= ~(LOCAL|LOCAL_COPY); vpbase = (vp->flag & ARRAY) ? global(arrayname(tvar)) : 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? */ errorfx(2, "read-only: %s", tvar); afree(tvar, ATEMP); /* most calls are with set/clr == 0 */ if (set | clr) { bool ok = true; /* * 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) { bool 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 = false; 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) errorfz(); } if (val != NULL) { char *tval; if (vappend) { tval = shf_smprintf("%s%s", str_val(vp), val); val = tval; } else tval = 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); afree(tval, ATEMP); } /* only x[0] is ever exported, so use vpbase */ if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER) && vpbase->type == 0) exportprep(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null); return (vp); } /** * Unset a variable. The flags can be: * |1 = tear down entire array * |2 = keep attributes, only unset content */ void unset(struct tbl *vp, int flags) { if (vp->flag & ALLOC) afree(vp->val.s, vp->areap); if ((vp->flag & ARRAY) && (flags & 1)) { 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 (flags & 2) { vp->flag &= ~(ALLOC|ISSET); return; } /* if foo[0] is being unset, the remainder of the array is kept... */ vp->flag &= SPECIAL | ((flags & 1) ? 0 : ARRAY|DEFINED); if (vp->flag & SPECIAL) /* responsible for 'unspecial'ing var */ unsetspec(vp); } /* * 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 NUL if whole string is legal). */ const char * skip_varname(const char *s, bool aok) { size_t alen; if (s && ksh_isalphx(*s)) { while (*++s && ksh_isalnux(*s)) ; if (aok && *s == '[' && (alen = array_ref_len(s))) s += alen; } return (s); } /* Return a pointer to the first character past any legal variable name */ const char * skip_wdvarname(const char *s, /* skip array de-reference? */ bool aok) { if (s[0] == CHAR && ksh_isalphx(s[1])) { do { s += 2; } while (s[0] == CHAR && ksh_isalnux(s[1])); if (aok && s[0] == CHAR && s[1] == '[') { /* skip possible array de-reference */ const char *p = s; char c; int depth = 0; while (/* CONSTCOND */ 1) { if (p[0] != CHAR) break; c = p[1]; p += 2; if (c == '[') depth++; else if (c == ']' && --depth == 0) { s = p; break; } } } } return (s); } /* Check if coded string s is a variable name */ int is_wdvarname(const char *s, bool aok) { const 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) { const char *p = skip_wdvarname(s, true); return (p != s && p[0] == CHAR && (p[1] == '=' || (p[1] == '+' && p[2] == CHAR && p[3] == '='))); } /* * Make the exported environment from the exported names in the dictionary. */ char ** makenv(void) { ssize_t i; struct block *l; XPtrV denv; struct tbl *vp, **vpp; XPinit(denv, 64); for (l = e->loc; l != NULL; l = l->next) { vpp = l->vars.tbls; i = 1 << (l->vars.tshift); while (--i >= 0) if ((vp = *vpp++) != NULL && (vp->flag&(ISSET|EXPORT)) == (ISSET|EXPORT)) { struct block *l2; struct tbl *vp2; uint32_t 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|SPECIAL); /* setstr can't fail here */ setstr(vp, val, KSH_RETURN_ERROR); } XPput(denv, vp->val.s); } if (l->flags & BF_STOPENV) break; } XPput(denv, NULL); return ((char **)XPclose(denv)); } /* * 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 mksh_uari_t user_lineno; /* what user set $LINENO to */ static void getspec(struct tbl *vp) { mksh_ari_u num; int st; struct timeval tv; switch ((st = special(vp->name))) { case V_COLUMNS: case V_LINES: /* * Do NOT export COLUMNS/LINES. Many applications * check COLUMNS/LINES before checking ws.ws_col/row, * so if the app is started with C/L in the environ * and the window is then resized, the app won't * see the change cause the environ doesn't change. */ if (got_winch) change_winsz(); break; } switch (st) { case V_BASHPID: num.u = (mksh_uari_t)procpid; break; case V_COLUMNS: num.i = x_cols; break; case V_HISTSIZE: num.i = histsize; break; case V_LINENO: num.u = (mksh_uari_t)current_lineno + user_lineno; break; case V_LINES: num.i = x_lins; break; case V_EPOCHREALTIME: { /* 10(%u) + 1(.) + 6 + NUL */ char buf[18]; vp->flag &= ~SPECIAL; mksh_TIME(tv); shf_snprintf(buf, sizeof(buf), "%u.%06u", (unsigned)tv.tv_sec, (unsigned)tv.tv_usec); setstr(vp, buf, KSH_RETURN_ERROR | 0x4); vp->flag |= SPECIAL; return; } case V_OPTIND: num.i = user_opt.uoptind; break; case V_RANDOM: num.i = rndget(); break; case V_SECONDS: /* * On start up the value of SECONDS is used before * it has been set - don't do anything in this case * (see initcoms[] in main.c). */ if (vp->flag & ISSET) { mksh_TIME(tv); num.i = tv.tv_sec - seconds; } else return; break; default: /* do nothing, do not touch vp at all */ return; } vp->flag &= ~SPECIAL; setint_n(vp, num.i, 0); vp->flag |= SPECIAL; } static void setspec(struct tbl *vp) { mksh_ari_u num; char *s; int st; switch ((st = special(vp->name))) { #if HAVE_PERSISTENT_HISTORY case V_HISTFILE: sethistfile(str_val(vp)); return; #endif case V_IFS: setctypes(s = str_val(vp), C_IFS); ifs0 = *s; return; case V_PATH: afree(path, APERM); s = str_val(vp); strdupx(path, s, APERM); /* clear tracked aliases */ flushcom(true); return; case V_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); /* LINTED use of access */ if (mksh_abspath(s) && access(s, W_OK|X_OK) == 0 && stat(s, &statb) == 0 && S_ISDIR(statb.st_mode)) strdupx(tmpdir, s, APERM); } return; /* common sub-cases */ case V_COLUMNS: case V_LINES: if (vp->flag & IMPORT) { /* do not touch */ unspecial(vp->name); vp->flag &= ~SPECIAL; return; } /* FALLTHROUGH */ case V_HISTSIZE: case V_LINENO: case V_OPTIND: case V_RANDOM: case V_SECONDS: case V_TMOUT: vp->flag &= ~SPECIAL; if (getint(vp, &num, false) == -1) { s = str_val(vp); if (st != V_RANDOM) errorf("%s: %s: %s", vp->name, "bad number", s); num.u = hash(s); } vp->flag |= SPECIAL; break; default: /* do nothing, do not touch vp at all */ return; } /* process the singular parts of the common cases */ switch (st) { case V_COLUMNS: if (num.i >= MIN_COLS) x_cols = num.i; break; case V_HISTSIZE: sethistsize(num.i); break; case V_LINENO: /* The -1 is because line numbering starts at 1. */ user_lineno = num.u - (mksh_uari_t)current_lineno - 1; break; case V_LINES: if (num.i >= MIN_LINS) x_lins = num.i; break; case V_OPTIND: getopts_reset((int)num.i); break; case V_RANDOM: /* * mksh R39d+ no longer has the traditional repeatability * of $RANDOM sequences, but always retains state */ rndset((unsigned long)num.u); break; case V_SECONDS: { struct timeval tv; mksh_TIME(tv); seconds = tv.tv_sec - num.i; } break; case V_TMOUT: ksh_tmout = num.i >= 0 ? num.i : 0; break; } } static void unsetspec(struct tbl *vp) { /* * 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 HISTSIZE, HISTFILE. Unsetting these in AT&T ksh does not * loose the 'specialness': IFS, COLUMNS, PATH, TMPDIR */ switch (special(vp->name)) { #if HAVE_PERSISTENT_HISTORY case V_HISTFILE: sethistfile(NULL); return; #endif case V_IFS: setctypes(TC_IFSWS, C_IFS); ifs0 = ' '; break; case V_PATH: afree(path, APERM); strdupx(path, def_path, APERM); /* clear tracked aliases */ flushcom(true); break; case V_TMPDIR: /* should not become unspecial */ if (tmpdir) { afree(tmpdir, APERM); tmpdir = NULL; } break; case V_LINENO: case V_RANDOM: case V_SECONDS: case V_TMOUT: /* AT&T ksh leaves previous value in place */ unspecial(vp->name); break; } } /* * Search for (and possibly create) a table entry starting with * vp, indexed by val. */ struct tbl * arraysearch(struct tbl *vp, uint32_t val) { struct tbl *prev, *curr, *news; size_t len; vp->flag = (vp->flag | (ARRAY | DEFINED)) & ~ASSOC; /* the table entry is always [0] */ if (val == 0) return (vp); prev = vp; curr = vp->u.array; while (curr && curr->ua.index < val) { prev = curr; curr = curr->u.array; } if (curr && curr->ua.index == val) { if (curr->flag&ISSET) return (curr); news = curr; } else news = NULL; if (!news) { len = strlen(vp->name); checkoktoadd(len, 1 + offsetof(struct tbl, name[0])); news = alloc(offsetof(struct tbl, name[0]) + ++len, vp->areap); memcpy(news->name, vp->name, len); } news->flag = (vp->flag & ~(ALLOC|DEFINED|ISSET|SPECIAL)) | AINDEX; news->type = vp->type; news->areap = vp->areap; news->u2.field = vp->u2.field; news->ua.index = val; if (curr != news) { /* not reusing old array entry */ prev->u.array = news; news->u.array = curr; } return (news); } /* * 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. * * XXX this should parse the actual arithmetic syntax */ size_t array_ref_len(const char *cp) { const char *s = cp; char 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; char *rv; if ((p = cstrchr(str, '[')) == 0) /* Shouldn't happen, but why worry? */ strdupx(rv, str, ATEMP); else strndupx(rv, str, p - str, ATEMP); return (rv); } /* set (or overwrite, if reset) the array variable var to the values in vals */ mksh_uari_t set_array(const char *var, bool reset, const char **vals) { struct tbl *vp, *vq; mksh_uari_t i = 0, j = 0; const char *ccp = var; char *cp = NULL; size_t n; /* to get local array, use "local foo; set -A foo" */ n = strlen(var); if (n > 0 && var[n - 1] == '+') { /* append mode */ reset = false; strndupx(cp, var, n - 1, ATEMP); ccp = cp; } vp = global(ccp); /* Note: AT&T ksh allows set -A but not set +A of a read-only var */ if ((vp->flag&RDONLY)) errorfx(2, "read-only: %s", ccp); /* This code is quite non-optimal */ if (reset) { /* trash existing values and attributes */ unset(vp, 1); /* allocate-by-access the [0] element to keep in scope */ arraysearch(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... */ if (cp != NULL) { /* find out where to set when appending */ for (vq = vp; vq; vq = vq->u.array) { if (!(vq->flag & ISSET)) continue; if (arrayindex(vq) >= j) j = arrayindex(vq) + 1; } afree(cp, ATEMP); } while ((ccp = vals[i])) { #if 0 /* temporarily taken out due to regression */ if (*ccp == '[') { int level = 0; while (*ccp) { if (*ccp == ']' && --level == 0) break; if (*ccp == '[') ++level; ++ccp; } if (*ccp == ']' && level == 0 && ccp[1] == '=') { strndupx(cp, vals[i] + 1, ccp - (vals[i] + 1), ATEMP); evaluate(substitute(cp, 0), (mksh_ari_t *)&j, KSH_UNWIND_ERROR, true); afree(cp, ATEMP); ccp += 2; } else ccp = vals[i]; } #endif vq = arraysearch(vp, j); /* would be nice to deal with errors here... (see above) */ setstr(vq, ccp, KSH_RETURN_ERROR); i++; j++; } return (i); } void change_winsz(void) { struct timeval tv; mksh_TIME(tv); BAFHUpdateMem_mem(qh_state, &tv, sizeof(tv)); #ifdef TIOCGWINSZ /* check if window size has changed */ if (tty_init_fd() < 2) { struct winsize ws; if (ioctl(tty_fd, TIOCGWINSZ, &ws) >= 0) { if (ws.ws_col) x_cols = ws.ws_col; if (ws.ws_row) x_lins = ws.ws_row; } } #endif /* bounds check for sane values, use defaults otherwise */ if (x_cols < MIN_COLS) x_cols = 80; if (x_lins < MIN_LINS) x_lins = 24; #ifdef SIGWINCH got_winch = 0; #endif } uint32_t hash(const void *s) { register uint32_t h; BAFHInit(h); BAFHUpdateStr_reg(h, s); BAFHFinish_reg(h); return (h); } uint32_t chvt_rndsetup(const void *bp, size_t sz) { register uint32_t h; /* use LCG as seed but try to get them to deviate immediately */ h = lcg_state; (void)rndget(); BAFHFinish_reg(h); /* variation through pid, ppid, and the works */ BAFHUpdateMem_reg(h, &rndsetupstate, sizeof(rndsetupstate)); /* some variation, some possibly entropy, depending on OE */ BAFHUpdateMem_reg(h, bp, sz); /* mix them all up */ BAFHFinish_reg(h); return (h); } mksh_ari_t rndget(void) { /* * this is the same Linear Congruential PRNG as Borland * C/C++ allegedly uses in its built-in rand() function */ return (((lcg_state = 22695477 * lcg_state + 1) >> 16) & 0x7FFF); } void rndset(unsigned long v) { register uint32_t h; #if defined(arc4random_pushb_fast) || defined(MKSH_A4PB) register uint32_t t; #endif struct { struct timeval tv; void *sp; uint32_t qh; pid_t pp; short r; } z; #ifdef DEBUG /* clear the allocated space, for valgrind */ memset(&z, 0, sizeof(z)); #endif h = lcg_state; BAFHFinish_reg(h); BAFHUpdateMem_reg(h, &v, sizeof(v)); mksh_TIME(z.tv); z.sp = &lcg_state; z.pp = procpid; z.r = (short)rndget(); #if defined(arc4random_pushb_fast) || defined(MKSH_A4PB) t = qh_state; BAFHFinish_reg(t); z.qh = (t & 0xFFFF8000) | rndget(); lcg_state = (t << 15) | rndget(); /* * either we have very chap entropy get and push available, * with malloc() pulling in this code already anyway, or the * user requested us to use the old functions */ t = h; BAFHUpdateMem_reg(t, &lcg_state, sizeof(lcg_state)); BAFHFinish_reg(t); lcg_state = t; #if defined(arc4random_pushb_fast) arc4random_pushb_fast(&lcg_state, sizeof(lcg_state)); lcg_state = arc4random(); #else lcg_state = arc4random_pushb(&lcg_state, sizeof(lcg_state)); #endif BAFHUpdateMem_reg(h, &lcg_state, sizeof(lcg_state)); #else z.qh = qh_state; #endif BAFHUpdateMem_reg(h, &z, sizeof(z)); BAFHFinish_reg(h); lcg_state = h; } void rndpush(const void *s) { register uint32_t h = qh_state; BAFHUpdateStr_reg(h, s); BAFHUpdateOctet_reg(h, 0); qh_state = h; }