aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--toys/pending/sh.c281
1 files changed, 159 insertions, 122 deletions
diff --git a/toys/pending/sh.c b/toys/pending/sh.c
index 4d698d6f..dda044d9 100644
--- a/toys/pending/sh.c
+++ b/toys/pending/sh.c
@@ -49,6 +49,7 @@
USE_SH(NEWTOY(cd, ">1LP[-LP]", TOYFLAG_NOFORK))
USE_SH(NEWTOY(exit, 0, TOYFLAG_NOFORK))
+USE_SH(NEWTOY(unset, "fvn", TOYFLAG_NOFORK))
USE_SH(NEWTOY(sh, "(noediting)(noprofile)(norc)sc:i", TOYFLAG_BIN))
USE_SH(OLDTOY(toysh, sh, TOYFLAG_BIN))
@@ -92,6 +93,17 @@ config EXIT
Exit shell. If no return value supplied on command line, use value
of most recent command, or 0 if none.
+
+config UNSET
+ bool
+ default n
+ depends on SH
+ help
+ usage: unset [-fvn] NAME...
+
+ -f NAME is a function
+ -v NAME is a variable
+ -n dereference NAME and unset that
*/
#define FOR_sh
@@ -101,7 +113,7 @@ GLOBALS(
char *c;
long lineno;
- char **locals, *subshell_env;
+ char **locals, *subshell_env, *ifs;
struct double_list functions;
unsigned options, jobcnt, loc_ro, loc_magic;
int hfd; // next high filehandle (>= 10)
@@ -161,6 +173,25 @@ void array_add(char ***list, unsigned count, char *data)
(*list)[count+1] = 0;
}
+// add argument to an arg_list
+void add_arg(struct arg_list **list, char *arg)
+{
+ struct arg_list *al;
+
+ if (!list) return;
+ al = xmalloc(sizeof(struct arg_list));
+ al->next = *list;
+ al->arg = arg;
+ *list = al;
+}
+
+void array_add_del(char ***list, unsigned count, char *data,
+ struct arg_list **delete)
+{
+ if (delete) add_arg(delete, data);
+ array_add(list, count, data);
+}
+
// Return index of variable within this list
static unsigned findvar(char **list, char *name, int len)
{
@@ -188,6 +219,8 @@ static void setvar(char *s, unsigned type)
if (type&TAKE_MEM) type ^= TAKE_MEM;
else s = xstrdup(s);
+ if (len == 3 && !memcmp(s, "IFS", 3)) TT.ifs = s+4;
+
// local, export, readonly, integer...
// exported variable?
@@ -202,7 +235,7 @@ static void setvar(char *s, unsigned type)
}
// get variable of length len starting at s.
-static char *getvarlen(char *s, int len)
+static char *getvarbylen(char *s, int len)
{
int i;
@@ -216,7 +249,7 @@ static char *getvarlen(char *s, int len)
static char *getvar(char *s)
{
- return getvarlen(s, strlen(s));
+ return getvarbylen(s, strlen(s));
}
// TODO: make parse_word use this?
@@ -252,18 +285,6 @@ int skip_quote(char *s)
return i;
}
-// add argument to an arg_list
-void add_arg(struct arg_list **list, char *arg)
-{
- struct arg_list *al;
-
- if (!list) return;
- al = xmalloc(sizeof(struct arg_list));
- al->next = *list;
- al->arg = arg;
- *list = al;
-}
-
// Return next available high (>=10) file descriptor
int next_hfd()
{
@@ -310,6 +331,7 @@ if (BUGBUG) dprintf(255, "%d redir from=%d to=%d hfd=%d\n", getpid(), from, to,
}
// TODO: waitpid(WNOHANG) to clean up zombies and catch background& ending
+// TODO: xunsetenv() after vfork()?
static void subshell_callback(void)
{
TT.subshell_env = xmprintf("@%d,%d=", getpid(), getppid());
@@ -388,23 +410,23 @@ int pipe_subshell(char *s, int len, int out)
}
// utf8 strchr: return wide char matched at wc from chrs, or 0 if not matched
-// if len, save length of wc when matched
+// if len, save length of wc
static int utf8chr(char *wc, char *chrs, int *len)
{
wchar_t wc1, wc2;
int ll;
+ if (len) *len = 1;
if (!*wc) return 0;
-
- ll = utf8towc(&wc1, wc, 99);
- if (ll<0 || wc1<1) {
- if (len) ++*len;
- return *wc;
- }
- if (wc1 > 0) {
+ if (0<(ll = utf8towc(&wc1, wc, 99))) {
if (len) *len = ll;
- while (*(chrs += utf8towc(&wc2, chrs, 99))) if (wc1 == wc2) break;
- if (*chrs) return wc1;
+ while (*chrs) {
+ if(1>(ll = utf8towc(&wc2, chrs, 99))) chrs++;
+ else {
+ if (wc1 == wc2) return wc1;
+ chrs += ll;
+ }
+ }
}
return 0;
@@ -426,51 +448,6 @@ static char *utf8spnc(char *str, char *chrs, int c)
return str;
}
-
-// This reeeeeally wants to be inline because we marshall half the function's
-// state to it and it write _back_ to more than one. End of loop?
-
-// Perform word splitting via $IFS, adding split chunks
-// Returns newly allocated end chunk.
-// input *off is length of new, output *off = resolved length
-static char *split_add(struct sh_arg *arg, struct arg_list **delete,
- char *before, char *new, char *after, char quote, int *off)
-{
-// TODO TT.ifs
- char *ifs = getenv("IFS"), *end = new;
- int i, j, len;
-
- if (!ifs) ifs = " \t\n";
-
- if (!(quote&1)) while (*new && *(end = utf8spnc(new, ifs, 1))) {
- new = xmprintf("%.*s%.*s", *off, before, (int)(end-new), new);
- *off = 0;
- for (j = 0; (i = utf8chr(end, ifs, &len)); end += len) {
-
- // runs of space allowed/collapsed before and after non-whitespace IFS
- if (!(j&1)) {
- if (iswspace(i)) {
- if (!j && new && !*new && !quote) {
- free(new);
- new = 0;
- }
- } else if (++j == 3) break;
- } else j++;
- }
- if (new) {
- add_arg(delete, new);
- array_add(&arg->v, arg->c++, new);
- quote = 0;
- }
- new = end;
- }
-
- end = xmprintf("%.*s%s%s", *off, before, new, after);
- *off += strlen(new);
-
- return end;
-}
-
#define NO_PATH (1<<0) // path expansion (wildcards)
#define NO_SPLIT (1<<1) // word splitting
#define NO_BRACE (1<<2) // {brace,expansion}
@@ -489,8 +466,8 @@ static char *split_add(struct sh_arg *arg, struct arg_list **delete,
static void expand_arg_nobrace(struct sh_arg *arg, char *str, unsigned flags,
struct arg_list **delete)
{
- char cc, qq = 0, *old = str, *new = str, *s, *ss;
- int ii = 0, jj, kk, oo;
+ char cc, qq = 0, *old = str, *new = str, *s, *ss, *ifs = 0, *del = 0;
+ int at = 0, ii = 0, dd, jj, kk, ll, oo;
if (BUGBUG) dprintf(255, "expand %s\n", str);
if (flags&FORCE_KEEP) old = 0;
@@ -520,7 +497,8 @@ if (BUGBUG) dprintf(255, "expand %s\n", str);
// parameter/variable expansion, and dequoting
- for (oo = 0; (cc = str[ii++]); old != new && (new[oo] = 0)) {
+ for (oo = 0; (cc = str[ii++]); old!=new && (new[oo] = 0)) {
+
// skip literal chars
if (!strchr("$'`\\\"", cc)) {
if (old != new) new[oo++] = cc;
@@ -550,74 +528,103 @@ if (BUGBUG) dprintf(255, "expand %s\n", str);
// TODO what does \ in `` mean? What is echo `printf %s \$x` supposed to do?
jj = pipe_subshell(str+ii+1+jj, kk-2-jj, 1);
ii += kk;
- ss = readfd(jj, 0, 0);
+ if ((ifs = del = readfd(jj, 0, 0)))
+ for (kk = strlen(ifs); kk && ifs[kk-1]=='\n'; ifs[--kk] = 0);
close(jj);
- if (ss && *ss) {
- kk = strlen(ss);
- while (kk && ss[kk-1]=='\n') ss[--kk] = 0;
-
- s = split_add(arg, delete, new, ss, str+ii, qq, &oo);
- if (new != old) free(new);
- new = s;
- }
- // Blank subshells don't add an argument.
- if (!str[ii]) {
- if (new != old) free(new);
- new = 0;
- }
} else if (cc == '$') {
- char buf[16];
- s = buf;
// *@#?-$!_0 "Special Paremeters" ($0 not affected by shift)
-
if (!(cc = str[ii++])) {
new[oo++] = cc;
break;
- } else if (cc == '?') {
- char buf[16];
- sprintf(buf, "%d", toys.exitval);
-
- s = split_add(arg, delete, new, buf, str+ii, qq, &oo);
- if (new != old) free(new);
- new = s;
- } else if (cc == '*' || cc == '@') {
- // Quoted agglomeration
+ } else if (cc == '?') ifs = del = xmprintf("%d", toys.exitval);
+ else if (cc == '#') ifs = del = xmprintf("%d", TT.arg->c?TT.arg->c-1:0);
+ else if (cc == '*' || cc == '@') {
+ // If not doing word split, handle here
if ((qq&1) && cc=='*') {
+//TODO separator is first char of IFS, not space: ll = utf8towc(&wc1, wc, 99);
+
for (jj = kk = 0; jj<TT.arg->c; jj++) kk += strlen(TT.arg->v[jj]);
s = xmalloc(oo+kk+TT.arg->c+strlen(str+ii)+1);
memcpy(s, new, oo);
- for (jj = 0; jj<TT.arg->c; jj++)
+ for (jj = 1; jj<TT.arg->c; jj++)
oo += sprintf(s+oo, " %s"+!jj, TT.arg->v[jj]);
strcpy(s+oo, str+ii);
- } else for (jj = 0; jj<TT.arg->c; jj++) {
- s = split_add(arg, delete, new, TT.arg->v[jj],
- jj+1==TT.arg->c ? str+ii : "", qq, &oo);
- if (new != old) free(new);
- new = s;
- }
+
+ // otherwise hand off to IFS logic at end of loop.
+ } else at = 1;
} else if(isdigit(cc)) {
for (kk = 0, ii--; isdigit(cc = str[ii]); ii++) kk = (10*kk)+cc-'0';
- s = split_add(arg, delete, new, kk<TT.arg->c ? TT.arg->v[kk] : "",
- str+ii, qq, &oo);
- if (new != old) free(new);
- new = s;
+ if (kk<TT.arg->c) ifs = TT.arg->v[kk];
- // TODO: ${ $(( $( $[ $'
+ // TODO: ${ $(( $[ $'
// } else if (cc == '{') {
} else {
s = str+--ii;
for (jj = 0; s[jj] && (s[jj]=='_' || !ispunct(s[jj])); jj++);
- s = jj ? getvarlen(str+ii, jj) : 0;
- s = xstrdup(s ? s : "");
+ if (!jj) new[oo++] = '$';
+// TODO: $((a=42)) can change var, affect lifetime here
+ else ifs = getvarbylen(str+ii, jj);
ii += jj;
- s = split_add(arg, delete, new, s, str+ii, qq, &oo);
- if (new != old) free(new);
- new = s;
}
}
+
+ // combine before/ifs/after sections, splitting words on $IFS in ifs
+ if (ifs || at) {
+ if (!at && !*ifs && !qq) continue;
+
+ // when at!=0, loop through argv for "$@". Otherwise process ifs as-is
+ do {
+
+ // get next argument, is this last entry, first IFS separator character
+ if (at) ifs = TT.arg->v[at++];
+ kk = !at || at==TT.arg->c;
+ ss = (qq&1) ? ifs+strlen(ifs) : utf8spnc(ifs, TT.ifs, 1);
+
+ // loop within current ifs due to word break
+ do {
+ // fast path: no new allocation when no prefix, no separator,
+ // and either not last entry or no suffix
+ if (!oo && !*ss && (!kk || !str[ii])) {
+ if (!qq && ss==ifs) break;
+ dd = !!del;
+ del = 0;
+ } else {
+ // combine prefix, ifs before separator, and suffix (as appropriate)
+ ifs = xmprintf("%.*s%.*s%s", oo, new, ll = ss-ifs, ifs,
+ (jj = (kk && !*ss)) ? str+ii : "");
+ if (old != new) free(new);
+ new = 0;
+ dd = 1;
+ if (jj) {
+ oo += ll;
+ new = ifs;
+
+ break;
+ } else oo = 0;
+
+ // combine whitespace separators
+ while ((jj = utf8chr(ss, TT.ifs, &ll)) && iswspace(jj)) ss += ll;
+
+ // add argument if quoted, non-blank, or non-whitespace separator
+ if (!qq && !*ifs && !*ss) {
+ free(ifs);
+
+ continue;
+ }
+ }
+
+ array_add_del(&arg->v, arg->c++, ifs, dd ? delete : 0);
+ qq &= 1;
+ } while (*(ifs = ss));
+ } while (!kk);
+
+ free(del);
+ ifs = del = 0;
+ at = 0;
+ }
}
// TODO globbing * ? [
@@ -632,8 +639,7 @@ if (BUGBUG) dprintf(255, "expand %s\n", str);
// Record result.
if (*new || qq) {
if (old==new && (flags&FORCE_COPY)) new = xstrdup(new);
- if (old!=new) add_arg(delete, new);
- array_add(&arg->v, arg->c++, new);
+ array_add_del(&arg->v, arg->c++, new, (old != new) ? delete : 0);
} else if(old != new) free(new);
}
@@ -901,7 +907,7 @@ static struct sh_process *expand_redir(struct sh_arg *arg, int envlen, int *urd)
// Handle <() >() redirectionss
if ((*s == '<' || *s == '>') && s[1] == '(') {
- int new = pipe_subshell(s+2, strlen(s+1)-1, *s == '>');
+ int new = pipe_subshell(s+2, strlen(s+2)-1, *s == '>');
// Grab subshell data
if (new == -1) {
@@ -913,8 +919,8 @@ static struct sh_process *expand_redir(struct sh_arg *arg, int envlen, int *urd)
// bash uses /dev/fd/%d which requires /dev/fd to be a symlink to
// /proc/self/fd so we just produce that directly.
- add_arg(&pp->delete, ss = xmprintf("/proc/self/fd/%d", new));
- array_add(&pp->arg.v, pp->arg.c++, ss);
+ array_add_del(&pp->arg.v, pp->arg.c++,
+ ss = xmprintf("/proc/self/fd/%d", new), &pp->delete);
continue;
}
@@ -951,7 +957,7 @@ static struct sh_process *expand_redir(struct sh_arg *arg, int envlen, int *urd)
else if (*s == '{') {
// when we close a filehandle, we _read_ from {var}, not write to it
if ((!strcmp(ss, "<&") || !strcmp(ss, ">&")) && !strcmp(sss, "-")) {
- if (!(ss = getvarlen(s+1, ss-s-2))) break;
+ if (!(ss = getvarbylen(s+1, ss-s-2))) break;
to = atoi(ss); // TODO trailing garbage?
if (save_redirect(&pp->urd, -1, to)) break;
close(to);
@@ -2105,6 +2111,7 @@ void subshell_setup(void)
// Ensure environ copied and toys.envc set, and clean out illegal entries
xunsetenv("");
+ TT.ifs = " \t\n";
for (to = from = 0; (s = environ[from]); from++) {
// If nommu subshell gets handoff
@@ -2117,6 +2124,7 @@ void subshell_setup(void)
// Filter out non-shell variable names
for (len = 0; s[len] && ((s[len] == '_') || !ispunct(s[len])); len++);
if (s[len] == '=') environ[to++] = environ[from];
+ if (!memcmp(s, "IFS=", 4)) TT.ifs = s+4;
}
environ[toys.optc = to] = 0;
@@ -2306,3 +2314,32 @@ void exit_main(void)
{
exit(*toys.optargs ? atoi(*toys.optargs) : 0);
}
+
+void unset_main(void)
+{
+ char **arg;
+ unsigned vv, xx;
+
+ for (arg = toys.optargs; *arg; arg++) {
+ if (!strcmp(*arg, "IFS")) TT.ifs = " \t\n";
+ if (strchr(*arg, '=')) error_msg("bad '%s'", *arg);
+ else {
+
+ // find and unset local
+ vv = findvar(TT.locals, *arg, strlen(*arg));
+ if (vv<TT.loc_ro || vv<TT.loc_magic) error_msg("nope"); // TODO this
+ else {
+ for (xx = vv; TT.locals[xx]; xx++);
+ if (xx) {
+ free(TT.locals[vv]);
+ memmove(TT.locals+vv, TT.locals+xx+1, xx);
+
+ continue;
+ }
+ }
+
+ // unset global
+ xsetenv(*arg, 0);
+ }
+ }
+}