diff options
| -rw-r--r-- | toys/pending/sh.c | 281 |
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); + } + } +} |