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Diffstat (limited to 'bin/1sh/var.c')
| -rw-r--r-- | bin/1sh/var.c | 971 |
1 files changed, 971 insertions, 0 deletions
diff --git a/bin/1sh/var.c b/bin/1sh/var.c new file mode 100644 index 00000000..2c217399 --- /dev/null +++ b/bin/1sh/var.c @@ -0,0 +1,971 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kenneth Almquist. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +#if 0 +static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95"; +#endif +#endif /* not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD: releng/12.1/bin/sh/var.c 329221 2018-02-13 16:48:57Z bdrewery $"); + +#include <unistd.h> +#include <stdlib.h> +#include <paths.h> + +/* + * Shell variables. + */ + +#include <locale.h> +#include <langinfo.h> + +#include "shell.h" +#include "output.h" +#include "expand.h" +#include "nodes.h" /* for other headers */ +#include "eval.h" /* defines cmdenviron */ +#include "exec.h" +#include "syntax.h" +#include "options.h" +#include "mail.h" +#include "var.h" +#include "memalloc.h" +#include "error.h" +#include "mystring.h" +#include "parser.h" +#include "builtins.h" +#ifndef NO_HISTORY +#include "myhistedit.h" +#endif + + +#ifndef VTABSIZE +#define VTABSIZE 39 +#endif + + +struct varinit { + struct var *var; + int flags; + const char *text; + void (*func)(const char *); +}; + + +#ifndef NO_HISTORY +struct var vhistsize; +struct var vterm; +#endif +struct var vifs; +struct var vmail; +struct var vmpath; +struct var vpath; +struct var vps1; +struct var vps2; +struct var vps4; +static struct var voptind; +struct var vdisvfork; + +struct localvar *localvars; +int forcelocal; + +static const struct varinit varinit[] = { +#ifndef NO_HISTORY + { &vhistsize, VUNSET, "HISTSIZE=", + sethistsize }, +#endif + { &vifs, 0, "IFS= \t\n", + NULL }, + { &vmail, VUNSET, "MAIL=", + NULL }, + { &vmpath, VUNSET, "MAILPATH=", + NULL }, + { &vpath, 0, "PATH=" _PATH_DEFPATH, + changepath }, + /* + * vps1 depends on uid + */ + { &vps2, 0, "PS2=> ", + NULL }, + { &vps4, 0, "PS4=+ ", + NULL }, +#ifndef NO_HISTORY + { &vterm, VUNSET, "TERM=", + setterm }, +#endif + { &voptind, 0, "OPTIND=1", + getoptsreset }, + { &vdisvfork, VUNSET, "SH_DISABLE_VFORK=", + NULL }, + { NULL, 0, NULL, + NULL } +}; + +static struct var *vartab[VTABSIZE]; + +static const char *const locale_names[7] = { + "LC_COLLATE", "LC_CTYPE", "LC_MONETARY", + "LC_NUMERIC", "LC_TIME", "LC_MESSAGES", NULL +}; +static const int locale_categories[7] = { + LC_COLLATE, LC_CTYPE, LC_MONETARY, LC_NUMERIC, LC_TIME, LC_MESSAGES, 0 +}; + +static int varequal(const char *, const char *); +static struct var *find_var(const char *, struct var ***, int *); +static int localevar(const char *); +static void setvareq_const(const char *s, int flags); + +extern char **environ; + +/* + * This routine initializes the builtin variables and imports the environment. + * It is called when the shell is initialized. + */ + +void +initvar(void) +{ + char ppid[20]; + const struct varinit *ip; + struct var *vp; + struct var **vpp; + char **envp; + + for (ip = varinit ; (vp = ip->var) != NULL ; ip++) { + if (find_var(ip->text, &vpp, &vp->name_len) != NULL) + continue; + vp->next = *vpp; + *vpp = vp; + vp->text = __DECONST(char *, ip->text); + vp->flags = ip->flags | VSTRFIXED | VTEXTFIXED; + vp->func = ip->func; + } + /* + * PS1 depends on uid + */ + if (find_var("PS1", &vpp, &vps1.name_len) == NULL) { + vps1.next = *vpp; + *vpp = &vps1; + vps1.text = __DECONST(char *, geteuid() ? "PS1=$ " : "PS1=# "); + vps1.flags = VSTRFIXED|VTEXTFIXED; + } + fmtstr(ppid, sizeof(ppid), "%d", (int)getppid()); + setvarsafe("PPID", ppid, 0); + for (envp = environ ; *envp ; envp++) { + if (strchr(*envp, '=')) { + setvareq(*envp, VEXPORT|VTEXTFIXED); + } + } + setvareq_const("OPTIND=1", 0); + setvareq_const("IFS= \t\n", 0); +} + +/* + * Safe version of setvar, returns 1 on success 0 on failure. + */ + +int +setvarsafe(const char *name, const char *val, int flags) +{ + struct jmploc jmploc; + struct jmploc *const savehandler = handler; + int err = 0; + int inton; + + inton = is_int_on(); + if (setjmp(jmploc.loc)) + err = 1; + else { + handler = &jmploc; + setvar(name, val, flags); + } + handler = savehandler; + SETINTON(inton); + return err; +} + +/* + * Set the value of a variable. The flags argument is stored with the + * flags of the variable. If val is NULL, the variable is unset. + */ + +void +setvar(const char *name, const char *val, int flags) +{ + const char *p; + size_t len; + size_t namelen; + size_t vallen; + char *nameeq; + int isbad; + + isbad = 0; + p = name; + if (! is_name(*p)) + isbad = 1; + p++; + for (;;) { + if (! is_in_name(*p)) { + if (*p == '\0' || *p == '=') + break; + isbad = 1; + } + p++; + } + namelen = p - name; + if (isbad) + error("%.*s: bad variable name", (int)namelen, name); + len = namelen + 2; /* 2 is space for '=' and '\0' */ + if (val == NULL) { + flags |= VUNSET; + vallen = 0; + } else { + vallen = strlen(val); + len += vallen; + } + INTOFF; + nameeq = ckmalloc(len); + memcpy(nameeq, name, namelen); + nameeq[namelen] = '='; + if (val) + memcpy(nameeq + namelen + 1, val, vallen + 1); + else + nameeq[namelen + 1] = '\0'; + setvareq(nameeq, flags); + INTON; +} + +static int +localevar(const char *s) +{ + const char *const *ss; + + if (*s != 'L') + return 0; + if (varequal(s + 1, "ANG")) + return 1; + if (strncmp(s + 1, "C_", 2) != 0) + return 0; + if (varequal(s + 3, "ALL")) + return 1; + for (ss = locale_names; *ss ; ss++) + if (varequal(s + 3, *ss + 3)) + return 1; + return 0; +} + + +/* + * Sets/unsets an environment variable from a pointer that may actually be a + * pointer into environ where the string should not be manipulated. + */ +static void +change_env(const char *s, int set) +{ + char *eqp; + char *ss; + + INTOFF; + ss = savestr(s); + if ((eqp = strchr(ss, '=')) != NULL) + *eqp = '\0'; + if (set && eqp != NULL) + (void) setenv(ss, eqp + 1, 1); + else + (void) unsetenv(ss); + ckfree(ss); + INTON; + + return; +} + + +/* + * Same as setvar except that the variable and value are passed in + * the first argument as name=value. Since the first argument will + * be actually stored in the table, it should not be a string that + * will go away. + */ + +void +setvareq(char *s, int flags) +{ + struct var *vp, **vpp; + int nlen; + + if (aflag) + flags |= VEXPORT; + if (forcelocal && !(flags & (VNOSET | VNOLOCAL))) + mklocal(s); + vp = find_var(s, &vpp, &nlen); + if (vp != NULL) { + if (vp->flags & VREADONLY) { + if ((flags & (VTEXTFIXED|VSTACK)) == 0) + ckfree(s); + error("%.*s: is read only", vp->name_len, vp->text); + } + if (flags & VNOSET) { + if ((flags & (VTEXTFIXED|VSTACK)) == 0) + ckfree(s); + return; + } + INTOFF; + + if (vp->func && (flags & VNOFUNC) == 0) + (*vp->func)(s + vp->name_len + 1); + + if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0) + ckfree(vp->text); + + vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET); + vp->flags |= flags; + vp->text = s; + + /* + * We could roll this to a function, to handle it as + * a regular variable function callback, but why bother? + * + * Note: this assumes iflag is not set to 1 initially. + * As part of initvar(), this is called before arguments + * are looked at. + */ + if ((vp == &vmpath || (vp == &vmail && ! mpathset())) && + iflag == 1) + chkmail(1); + if ((vp->flags & VEXPORT) && localevar(s)) { + change_env(s, 1); + (void) setlocale(LC_ALL, ""); + updatecharset(); + } + INTON; + return; + } + /* not found */ + if (flags & VNOSET) { + if ((flags & (VTEXTFIXED|VSTACK)) == 0) + ckfree(s); + return; + } + INTOFF; + vp = ckmalloc(sizeof (*vp)); + vp->flags = flags; + vp->text = s; + vp->name_len = nlen; + vp->next = *vpp; + vp->func = NULL; + *vpp = vp; + if ((vp->flags & VEXPORT) && localevar(s)) { + change_env(s, 1); + (void) setlocale(LC_ALL, ""); + updatecharset(); + } + INTON; +} + + +static void +setvareq_const(const char *s, int flags) +{ + setvareq(__DECONST(char *, s), flags | VTEXTFIXED); +} + + +/* + * Process a linked list of variable assignments. + */ + +void +listsetvar(struct arglist *list, int flags) +{ + int i; + + INTOFF; + for (i = 0; i < list->count; i++) + setvareq(savestr(list->args[i]), flags); + INTON; +} + + + +/* + * Find the value of a variable. Returns NULL if not set. + */ + +char * +lookupvar(const char *name) +{ + struct var *v; + + v = find_var(name, NULL, NULL); + if (v == NULL || v->flags & VUNSET) + return NULL; + return v->text + v->name_len + 1; +} + + + +/* + * Search the environment of a builtin command. If the second argument + * is nonzero, return the value of a variable even if it hasn't been + * exported. + */ + +char * +bltinlookup(const char *name, int doall) +{ + struct var *v; + char *result; + int i; + + result = NULL; + if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) { + if (varequal(cmdenviron->args[i], name)) + result = strchr(cmdenviron->args[i], '=') + 1; + } + if (result != NULL) + return result; + + v = find_var(name, NULL, NULL); + if (v == NULL || v->flags & VUNSET || + (!doall && (v->flags & VEXPORT) == 0)) + return NULL; + return v->text + v->name_len + 1; +} + + +/* + * Set up locale for a builtin (LANG/LC_* assignments). + */ +void +bltinsetlocale(void) +{ + int act = 0; + char *loc, *locdef; + int i; + + if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) { + if (localevar(cmdenviron->args[i])) { + act = 1; + break; + } + } + if (!act) + return; + loc = bltinlookup("LC_ALL", 0); + INTOFF; + if (loc != NULL) { + setlocale(LC_ALL, loc); + INTON; + updatecharset(); + return; + } + locdef = bltinlookup("LANG", 0); + for (i = 0; locale_names[i] != NULL; i++) { + loc = bltinlookup(locale_names[i], 0); + if (loc == NULL) + loc = locdef; + if (loc != NULL) + setlocale(locale_categories[i], loc); + } + INTON; + updatecharset(); +} + +/* + * Undo the effect of bltinlocaleset(). + */ +void +bltinunsetlocale(void) +{ + int i; + + INTOFF; + if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) { + if (localevar(cmdenviron->args[i])) { + setlocale(LC_ALL, ""); + updatecharset(); + break; + } + } + INTON; +} + +/* + * Update the localeisutf8 flag. + */ +void +updatecharset(void) +{ + char *charset; + + charset = nl_langinfo(CODESET); + localeisutf8 = !strcmp(charset, "UTF-8"); +} + +void +initcharset(void) +{ + updatecharset(); + initial_localeisutf8 = localeisutf8; +} + +/* + * Generate a list of exported variables. This routine is used to construct + * the third argument to execve when executing a program. + */ + +char ** +environment(void) +{ + int nenv; + struct var **vpp; + struct var *vp; + char **env, **ep; + + nenv = 0; + for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { + for (vp = *vpp ; vp ; vp = vp->next) + if (vp->flags & VEXPORT) + nenv++; + } + ep = env = stalloc((nenv + 1) * sizeof *env); + for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { + for (vp = *vpp ; vp ; vp = vp->next) + if (vp->flags & VEXPORT) + *ep++ = vp->text; + } + *ep = NULL; + return env; +} + + +static int +var_compare(const void *a, const void *b) +{ + const char *const *sa, *const *sb; + + sa = a; + sb = b; + /* + * This compares two var=value strings which creates a different + * order from what you would probably expect. POSIX is somewhat + * ambiguous on what should be sorted exactly. + */ + return strcoll(*sa, *sb); +} + + +/* + * Command to list all variables which are set. This is invoked from the + * set command when it is called without any options or operands. + */ + +int +showvarscmd(int argc __unused, char **argv __unused) +{ + struct var **vpp; + struct var *vp; + const char *s; + const char **vars; + int i, n; + + /* + * POSIX requires us to sort the variables. + */ + n = 0; + for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) { + for (vp = *vpp; vp; vp = vp->next) { + if (!(vp->flags & VUNSET)) + n++; + } + } + + INTOFF; + vars = ckmalloc(n * sizeof(*vars)); + i = 0; + for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) { + for (vp = *vpp; vp; vp = vp->next) { + if (!(vp->flags & VUNSET)) + vars[i++] = vp->text; + } + } + + qsort(vars, n, sizeof(*vars), var_compare); + for (i = 0; i < n; i++) { + /* + * Skip improper variable names so the output remains usable as + * shell input. + */ + if (!isassignment(vars[i])) + continue; + s = strchr(vars[i], '='); + s++; + outbin(vars[i], s - vars[i], out1); + out1qstr(s); + out1c('\n'); + } + ckfree(vars); + INTON; + + return 0; +} + + + +/* + * The export and readonly commands. + */ + +int +exportcmd(int argc __unused, char **argv) +{ + struct var **vpp; + struct var *vp; + char **ap; + char *name; + char *p; + char *cmdname; + int ch, values; + int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT; + + cmdname = argv[0]; + values = 0; + while ((ch = nextopt("p")) != '\0') { + switch (ch) { + case 'p': + values = 1; + break; + } + } + + if (values && *argptr != NULL) + error("-p requires no arguments"); + if (*argptr != NULL) { + for (ap = argptr; (name = *ap) != NULL; ap++) { + if ((p = strchr(name, '=')) != NULL) { + p++; + } else { + vp = find_var(name, NULL, NULL); + if (vp != NULL) { + vp->flags |= flag; + if ((vp->flags & VEXPORT) && localevar(vp->text)) { + change_env(vp->text, 1); + (void) setlocale(LC_ALL, ""); + updatecharset(); + } + continue; + } + } + setvar(name, p, flag); + } + } else { + for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { + for (vp = *vpp ; vp ; vp = vp->next) { + if (vp->flags & flag) { + if (values) { + /* + * Skip improper variable names + * so the output remains usable + * as shell input. + */ + if (!isassignment(vp->text)) + continue; + out1str(cmdname); + out1c(' '); + } + if (values && !(vp->flags & VUNSET)) { + outbin(vp->text, + vp->name_len + 1, out1); + out1qstr(vp->text + + vp->name_len + 1); + } else + outbin(vp->text, vp->name_len, + out1); + out1c('\n'); + } + } + } + } + return 0; +} + + +/* + * The "local" command. + */ + +int +localcmd(int argc __unused, char **argv __unused) +{ + char *name; + + nextopt(""); + if (! in_function()) + error("Not in a function"); + while ((name = *argptr++) != NULL) { + mklocal(name); + } + return 0; +} + + +/* + * Make a variable a local variable. When a variable is made local, it's + * value and flags are saved in a localvar structure. The saved values + * will be restored when the shell function returns. We handle the name + * "-" as a special case. + */ + +void +mklocal(char *name) +{ + struct localvar *lvp; + struct var **vpp; + struct var *vp; + + INTOFF; + lvp = ckmalloc(sizeof (struct localvar)); + if (name[0] == '-' && name[1] == '\0') { + lvp->text = ckmalloc(sizeof optval); + memcpy(lvp->text, optval, sizeof optval); + vp = NULL; + } else { + vp = find_var(name, &vpp, NULL); + if (vp == NULL) { + if (strchr(name, '=')) + setvareq(savestr(name), VSTRFIXED | VNOLOCAL); + else + setvar(name, NULL, VSTRFIXED | VNOLOCAL); + vp = *vpp; /* the new variable */ + lvp->text = NULL; + lvp->flags = VUNSET; + } else { + lvp->text = vp->text; + lvp->flags = vp->flags; + vp->flags |= VSTRFIXED|VTEXTFIXED; + if (name[vp->name_len] == '=') + setvareq(savestr(name), VNOLOCAL); + } + } + lvp->vp = vp; + lvp->next = localvars; + localvars = lvp; + INTON; +} + + +/* + * Called after a function returns. + */ + +void +poplocalvars(void) +{ + struct localvar *lvp; + struct var *vp; + int islocalevar; + + INTOFF; + while ((lvp = localvars) != NULL) { + localvars = lvp->next; + vp = lvp->vp; + if (vp == NULL) { /* $- saved */ + memcpy(optval, lvp->text, sizeof optval); + ckfree(lvp->text); + optschanged(); + } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) { + vp->flags &= ~VREADONLY; + (void)unsetvar(vp->text); + } else { + islocalevar = (vp->flags | lvp->flags) & VEXPORT && + localevar(lvp->text); + if ((vp->flags & VTEXTFIXED) == 0) + ckfree(vp->text); + vp->flags = lvp->flags; + vp->text = lvp->text; + if (vp->func) + (*vp->func)(vp->text + vp->name_len + 1); + if (islocalevar) { + change_env(vp->text, vp->flags & VEXPORT && + (vp->flags & VUNSET) == 0); + setlocale(LC_ALL, ""); + updatecharset(); + } + } + ckfree(lvp); + } + INTON; +} + + +int +setvarcmd(int argc, char **argv) +{ + if (argc <= 2) + return unsetcmd(argc, argv); + else if (argc == 3) + setvar(argv[1], argv[2], 0); + else + error("too many arguments"); + return 0; +} + + +/* + * The unset builtin command. + */ + +int +unsetcmd(int argc __unused, char **argv __unused) +{ + char **ap; + int i; + int flg_func = 0; + int flg_var = 0; + int ret = 0; + + while ((i = nextopt("vf")) != '\0') { + if (i == 'f') + flg_func = 1; + else + flg_var = 1; + } + if (flg_func == 0 && flg_var == 0) + flg_var = 1; + + INTOFF; + for (ap = argptr; *ap ; ap++) { + if (flg_func) + ret |= unsetfunc(*ap); + if (flg_var) + ret |= unsetvar(*ap); + } + INTON; + return ret; +} + + +/* + * Unset the specified variable. + * Called with interrupts off. + */ + +int +unsetvar(const char *s) +{ + struct var **vpp; + struct var *vp; + + vp = find_var(s, &vpp, NULL); + if (vp == NULL) + return (0); + if (vp->flags & VREADONLY) + return (1); + if (vp->text[vp->name_len + 1] != '\0') + setvar(s, "", 0); + if ((vp->flags & VEXPORT) && localevar(vp->text)) { + change_env(s, 0); + setlocale(LC_ALL, ""); + updatecharset(); + } + vp->flags &= ~VEXPORT; + vp->flags |= VUNSET; + if ((vp->flags & VSTRFIXED) == 0) { + if ((vp->flags & VTEXTFIXED) == 0) + ckfree(vp->text); + *vpp = vp->next; + ckfree(vp); + } + return (0); +} + + + +/* + * Returns true if the two strings specify the same variable. The first + * variable name is terminated by '='; the second may be terminated by + * either '=' or '\0'. + */ + +static int +varequal(const char *p, const char *q) +{ + while (*p == *q++) { + if (*p++ == '=') + return 1; + } + if (*p == '=' && *(q - 1) == '\0') + return 1; + return 0; +} + +/* + * Search for a variable. + * 'name' may be terminated by '=' or a NUL. + * vppp is set to the pointer to vp, or the list head if vp isn't found + * lenp is set to the number of characters in 'name' + */ + +static struct var * +find_var(const char *name, struct var ***vppp, int *lenp) +{ + unsigned int hashval; + int len; + struct var *vp, **vpp; + const char *p = name; + + hashval = 0; + while (*p && *p != '=') + hashval = 2 * hashval + (unsigned char)*p++; + len = p - name; + + if (lenp) + *lenp = len; + vpp = &vartab[hashval % VTABSIZE]; + if (vppp) + *vppp = vpp; + + for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) { + if (vp->name_len != len) + continue; + if (memcmp(vp->text, name, len) != 0) + continue; + if (vppp) + *vppp = vpp; + return vp; + } + return NULL; +} |