diff options
| -rw-r--r-- | toys/pending/sh.c | 399 |
1 files changed, 207 insertions, 192 deletions
diff --git a/toys/pending/sh.c b/toys/pending/sh.c index 22d991a5..0b2e85c1 100644 --- a/toys/pending/sh.c +++ b/toys/pending/sh.c @@ -146,7 +146,7 @@ GLOBALS( char **locals, *subshell_env, *ifs; struct double_list functions; unsigned options, jobcnt, loc_ro, loc_magic; - int hfd; // next high filehandle (>= 10) + int hfd, pid; // Running jobs for job control. struct sh_job { @@ -227,7 +227,7 @@ static void dump_state(struct sh_function *sp) while ((dd = readdir(dir))) { if (atoi(dd->d_name)!=fd && 0<readlinkat(fd, dd->d_name, buf,sizeof(buf))) - dprintf(2, "OPEN %d: %s = %s\n", getpid(), dd->d_name, buf); + dprintf(255, "OPEN %d: %s = %s\n", getpid(), dd->d_name, buf); } closedir(dir); } @@ -242,17 +242,10 @@ static const char *redirectors[] = {"<<<", "<<-", "<<", "<&", "<>", "<", ">>", #define SH_NOCLOBBER 1 // set -C -// like error_msg() but exit from shell scripts -static void syntax_err(char *msg, ...) +static void syntax_err(char *s) { - va_list va; - -// TODO rethink syntax errordom - va_start(va, msg); - verror_msg(msg, 0, va); - va_end(va); - - if (*toys.optargs) xexit(); + error_msg("syntax error: %s", s); + toys.exitval = 2; } // append to array with null terminator and realloc as necessary @@ -342,37 +335,125 @@ static char *getvar(char *s) return getvarbylen(s, strlen(s)); } -// TODO: make parse_word use this? -// returns length of current quote context. Handles \ '' "" `` $() -static int skip_quote(char *s) +// return length of match found at this point (try is null terminated array) +static int anystart(char *s, char **try) +{ + char *ss = s; + + while (*try) if (strstart(&s, *try++)) return s-ss; + + return 0; +} + +// does this entire string match one of the strings in try[] +static int anystr(char *s, char **try) +{ + while (*try) if (!strcmp(s, *try++)) return 1; + + return 0; +} + +// return length of valid prefix that could go before redirect +static int redir_prefix(char *word) +{ + char *s = word; + + if (*s == '{') { + for (s++; isalnum(*s) || *s=='_'; s++); + if (*s == '}' && s != word+1) s++; + else s = word; + } else while (isdigit(*s)) s++; + + return s-word; +} + +// parse next word from command line. Returns end, or 0 if need continuation +// caller eats leading spaces. If early, stop at first unquoted char. +static char *parse_word(char *start, int early) { - int i, q = 0; + int i, quote = 0, q, qc = 0; + char *end = start, *s; + + // Things we should only return at the _start_ of a word - // quotes were checked for balance and overflow by parse_word() - for (i = 0; s[i]; i++) { - char c = s[i], qq = q ? toybuf[q-1] : 0; + if (strstart(&end, "<(") || strstart(&end, ">(")) toybuf[quote++]=')'; + + // Redirections. 123<<file- parses as 2 args: "123<<" "file-". + s = end + redir_prefix(end); + if ((i = anystart(s, (void *)redirectors))) s += i; + if (s != end) return (end == start) ? s : end; - // backslash escapes skip a char, and return for EOL or unquoted. - if (c == '\\') { - if (qq!= '\'' && qq!='`') { - if (!s[++i]) return i; - if (!q) return ++i; + // (( is a special quote at the start of a word + if (strstart(&end, "((")) toybuf[quote++] = 255; + + // find end of this word + while (*end) { + i = 0; + + // barf if we're near overloading quote stack (nesting ridiculously deep) + if (quote>4000) { + syntax_err("tilt"); + return (void *)1; + } + + // Handle quote contexts + if ((q = quote ? toybuf[quote-1] : 0)) { + + // when waiting for parentheses, they nest + if ((q == ')' || q == '\xff') && (*end == '(' || *end == ')')) { + if (*end == '(') qc++; + else if (qc) qc--; + else if (q == '\xff') { + // (( can end with )) or retroactively become two (( if we hit one ) + if (strstart(&end, "))")) quote--; + else return start+1; + } else if (*end == ')') quote--; + end++; + + // end quote? + } else if (*end == q) quote--, end++; + + // single quote claims everything + else if (q == '\'') end++; + else i++; + + // loop if we already handled a symbol + if (!i) continue; + } else { + // Things that only matter when unquoted + + if (isspace(*end)) break; + if (*end == ')') return end+(start==end); + + // Flow control characters that end pipeline segments + s = end + anystart(end, (char *[]){";;&", ";;", ";&", ";", "||", + "|&", "|", "&&", "&", "(", ")", 0}); + if (s != end) return (end == start) ? s : end; + } + + // Things the same unquoted or in most non-single-quote contexts + + // start new quote context? + if (strchr("\"'`", *end)) toybuf[quote++] = *end++; + + // backslash escapes + else if (*end == '\\') { + if (!end[1] || (end[1]=='\n' && !end[2])) return 0; + end += 2; + } else if (*end == '$' && -1 != (i = stridx("({[", end[1]))) { + end++; + if (strstart(&end, "((")) toybuf[quote++] = 255; + else { + toybuf[quote++] = ")}]"[i]; + end++; } - // $( triggers anywhere but inside ' ' - } else if (qq!='\'' && c=='$' && s[1]=='(') { - toybuf[q++] = ')'; - i+=2; - // unquoted parentheses nest inside $(), I.E. "$(()" isn't done yet. - } else if (c=='(' && qq==')') toybuf[q++] = ')'; - // end current quoting context with match - else if (q && qq==c) q--; - // start new non-nesting quoting context only at top level - else if ((!q || qq==')') && (c=='"' || c=='\'' || c=='`')) toybuf[q++] = c; - - if (!q) break; + } else { + if (early && !quote) break; + end++; + } } - return i; + return quote ? 0 : end; } // Return next available high (>=10) file descriptor @@ -392,7 +473,8 @@ static int next_hfd() // Perform a redirect, saving displaced filehandle to a high (>10) fd // rd is an int array: [0] = count, followed by from/to pairs to restore later. -// If from == -1 just save to, else dup from->to after saving to. +// If from >= 0 dup from->to after saving to. If from == -1 just save to. +// if from == -2 schedule "to" to be closed by unredirect. static int save_redirect(int **rd, int from, int to) { int cnt, hfd, *rr; @@ -400,16 +482,21 @@ static int save_redirect(int **rd, int from, int to) if (from == to) return 0; // save displaced to, copying to high (>=10) file descriptor to undo later // except if we're saving to environment variable instead (don't undo that) - if ((hfd = next_hfd())==-1) return 1; - if (hfd != dup2(to, hfd)) hfd = -1; - else fcntl(hfd, F_SETFD, FD_CLOEXEC); - + if (from>-2) { + if ((hfd = next_hfd())==-1) return 1; + if (hfd != dup2(to, hfd)) hfd = -1; + else fcntl(hfd, F_SETFD, FD_CLOEXEC); if (BUGBUG) dprintf(255, "%d redir from=%d to=%d hfd=%d\n", getpid(), from, to, hfd); - // dup "to" - if (from != -1 && to != dup2(from, to)) { - if (hfd != -1) close(hfd); + // dup "to" + if (from >= 0 && to != dup2(from, to)) { + if (hfd >= 0) close(hfd); - return 1; + return 1; + } + } else { +dprintf(255, "%d schedule close %d\n", getpid(), to); + hfd = to; + to = -1; } // Append undo information to redirect list so we can restore saved hfd later. @@ -428,6 +515,8 @@ static void subshell_callback(void) TT.subshell_env = xmprintf("@%d,%d=", getpid(), getppid()); xsetenv(TT.subshell_env, 0); TT.subshell_env[strlen(TT.subshell_env)-1] = 0; + xsetenv(xmprintf("$=%d", TT.pid), 0); +// TODO: test $$ in (nommu) } // TODO check every caller of run_subshell for error, or syntax_error() here @@ -438,6 +527,7 @@ static int run_subshell(char *str, int len) { pid_t pid; +if (BUGBUG) dprintf(255, "run_subshell %.*s\n", len, str); // The with-mmu path is significantly faster. if (CFG_TOYBOX_FORK) { char *s; @@ -447,7 +537,6 @@ static int run_subshell(char *str, int len) s = xstrndup(str, len); sh_run(s); free(s); - _exit(toys.exitval); } @@ -482,8 +571,8 @@ static void unredirect(int *urd) if (!urd) return; for (i = 0; i<*urd; i++, rr += 2) { -if (BUGBUG) dprintf(255, "urd %d %d\n", rr[0], rr[1]); - if (rr[1] != -1) { +if (BUGBUG) dprintf(255, "%d urd %d %d\n", getpid(), rr[0], rr[1]); + if (rr[0] != -1) { // No idea what to do about fd exhaustion here, so Steinbach's Guideline. dup2(rr[0], rr[1]); close(rr[0]); @@ -504,10 +593,10 @@ static int pipe_subshell(char *s, int len, int out) return -1; } - // Perform input or output redirect and launch process + // Perform input or output redirect and launch process (ignoring errors) save_redirect(&uu, pipes[in], in); close(pipes[in]); - run_subshell(s, len); // ignore errors, don't track + run_subshell(s, len); unredirect(uu); return pipes[out]; @@ -646,15 +735,44 @@ if (BUGBUG) dprintf(255, "expand %s\n", str); } // both types of subshell work the same, so do $( here not in '$' below // TODO $((echo hello) | cat) ala $(( becomes $( ( retroactively - } else if (cc == '`' || (cc == '$' && str[ii] == '(' && str[ii+1] != '(')) { - kk = skip_quote(str+ii); - jj = cc == '$'; + } else if (cc == '`' || (cc == '$' && str[ii] == '(')) { + off_t pp = 0; + + s = str+ii-1; + kk = parse_word(str+ii-1, 1)-s; + if (*toybuf == 0xff) { + s += 3; + kk -= 5; +dprintf(2, "TODO: do math for %.*s\n", kk, s); + } else { + // Run subshell and trim trailing newlines + s += (jj = 1+(cc == '$')); + ii += --kk; + kk -= jj; + + // Special case echo $(<input) + for (ss = s; isspace(*ss); ss++); + if (*ss != '<') ss = 0; + else { + while (isspace(*++ss)); + if (!(ll = parse_word(ss, 0)-ss)) ss = 0; + else { + jj = ll+(ss-s); + while (isspace(s[jj])) jj++; + if (jj != kk) ss = 0; + else { + jj = xcreate_stdio(ss = xstrndup(ss, ll), O_RDONLY|WARN_ONLY, 0); + free(ss); + } + } + } + // TODO what does \ in `` mean? What is echo `printf %s \$x` supposed to do? - jj = pipe_subshell(str+ii+1+jj, kk-2-jj, 1); - ii += kk; - if ((ifs = del = readfd(jj, 0, 0))) - for (kk = strlen(ifs); kk && ifs[kk-1]=='\n'; ifs[--kk] = 0); - close(jj); + if (!ss) jj = pipe_subshell(s, kk, 1); + if ((ifs = del = readfd(jj, 0, &pp))) + for (kk = strlen(ifs); kk && ifs[kk-1]=='\n'; ifs[--kk] = 0); + close(jj); + } } else if (cc == '$') { // *@#?-$!_0 "Special Paremeters" ($0 not affected by shift) @@ -687,6 +805,7 @@ if (BUGBUG) dprintf(255, "expand %s\n", str); // TODO: ${ $(( $[ $' // } else if (cc == '{') { + // $VARIABLE } else { s = str+--ii; for (jj = 0; s[jj] && (s[jj]=='_' || !ispunct(s[jj])); jj++); @@ -782,7 +901,7 @@ static void expand_arg(struct sh_arg *arg, char *old, unsigned flags, // collect brace spans if (!(flags&NO_BRACE)) for (i = 0; ; i++) { - while ((j = skip_quote(old+i))) i += j; + while ((s = parse_word(old+i, 1)) != old+i) i += s-(old+i); if (!bb && !old[i]) break; if (bb && (!old[i] || old[i] == '}')) { bb->active = bb->commas[bb->cnt+1] = i; @@ -913,38 +1032,6 @@ static char *expand_one_arg(char *new, unsigned flags, struct arg_list **del) return s; } -// return length of match found at this point (try is null terminated array) -static int anystart(char *s, char **try) -{ - char *ss = s; - - while (*try) if (strstart(&s, *try++)) return s-ss; - - return 0; -} - -// does this entire string match one of the strings in try[] -static int anystr(char *s, char **try) -{ - while (*try) if (!strcmp(s, *try++)) return 1; - - return 0; -} - -// return length of valid prefix that could go before redirect -static int redir_prefix(char *word) -{ - char *s = word; - - if (*s == '{') { - for (s++; isalnum(*s) || *s=='_'; s++); - if (*s == '}' && s != word+1) s++; - else s = word; - } else while (isdigit(*s)) s++; - - return s-word; -} - // TODO |& // turn a parsed pipeline back into a string. @@ -1005,7 +1092,7 @@ static struct sh_process *expand_redir(struct sh_arg *arg, int envlen, int *urd) return pp; } - save_redirect(&urd, -1, new); + save_redirect(&pp->urd, -2, new); // bash uses /dev/fd/%d which requires /dev/fd to be a symlink to // /proc/self/fd so we just produce that directly. @@ -1124,7 +1211,7 @@ notfd: if (!strcmp(ss, "<>")) from = O_CREAT|O_RDWR; else if (strstr(ss, ">>")) from = O_CREAT|O_APPEND|O_WRONLY; else { - from = (*ss != '<') ? O_CREAT|O_WRONLY|O_TRUNC : O_RDONLY; + from = (*ss == '<') ? O_RDONLY : O_CREAT|O_WRONLY|O_TRUNC; if (!strcmp(ss, ">") && (TT.options&SH_NOCLOBBER)) { struct stat st; @@ -1138,7 +1225,11 @@ notfd: // TODO: /dev/{tcp,udp}/host/port // Open the file - if (-1 == (from = xcreate(sss, from|WARN_ONLY, 0666))) break; + if (-1 == (from = xcreate_stdio(sss, from|WARN_ONLY, 0666))) { + s = 0; + + break; + } } // perform redirect, saving displaced "to". @@ -1157,7 +1248,7 @@ notfd: // didn't parse everything? if (j != arg->c) { - syntax_err("bad %s", s); + if (s) syntax_err(s); if (!pp->exit) pp->exit = 1; free(cv); } @@ -1173,6 +1264,8 @@ static struct sh_process *run_command(struct sh_arg *arg) int envlen, j; char *s; +if (BUGBUG) dprintf(255, "run_command %s\n", arg->v[0]); + // Grab leading variable assignments for (envlen = 0; envlen<arg->c; envlen++) { s = arg->v[envlen]; @@ -1273,91 +1366,6 @@ static void free_process(void *ppp) free(pp); } - -// parse next word from command line. Returns end, or 0 if need continuation -// caller eats leading spaces -static char *parse_word(char *start) -{ - int i, quote = 0, q, qc = 0; - char *end = start, *s; - - // Things we should only return at the _start_ of a word - - if (strstart(&end, "<(") || strstart(&end, ">(")) toybuf[quote++]=')'; - - // Redirections. 123<<file- parses as 2 args: "123<<" "file-". - s = end + redir_prefix(end); - if ((i = anystart(s, (void *)redirectors))) s += i; - if (s != end) return (end == start) ? s : end; - - // (( is a special quote at the start of a word - if (strstart(&end, "((")) toybuf[quote++] = 255; - - // find end of this word - while (*end) { - i = 0; - - // barf if we're near overloading quote stack (nesting ridiculously deep) - if (quote>4000) { - syntax_err("tilt"); - return (void *)1; - } - - // Handle quote contexts - if ((q = quote ? toybuf[quote-1] : 0)) { - - // when waiting for parentheses, they nest - if ((q == ')' || q == '\xff') && (*end == '(' || *end == ')')) { - if (*end == '(') qc++; - else if (qc) qc--; - else if (q == '\xff') { - // (( can end with )) or retroactively become two (( if we hit one ) - if (strstart(&end, "))")) quote--; - else return start+1; - } else if (*end == ')') quote--; - end++; - - // end quote? - } else if (*end == q) quote--, end++; - - // single quote claims everything - else if (q == '\'') end++; - else i++; - - // loop if we already handled a symbol - if (!i) continue; - } else { - // Things that only matter when unquoted - - if (isspace(*end)) break; - if (*end == ')') return end+(start==end); - - // Flow control characters that end pipeline segments - s = end + anystart(end, (char *[]){";;&", ";;", ";&", ";", "||", - "|&", "|", "&&", "&", "(", ")", 0}); - if (s != end) return (end == start) ? s : end; - } - - // Things the same unquoted or in most non-single-quote contexts - - // start new quote context? - if (strchr("\"'`", *end)) toybuf[quote++] = *end++; - - // backslash escapes - else if (*end == '\\') { - if (!end[1] || (end[1]=='\n' && !end[2])) return 0; - end += 2; - } else if (*end++ == '$') { - if (-1 != (i = stridx("({[", *end))) { - toybuf[quote++] = ")}]"[i]; - end++; - } - } - } - - return quote ? 0 : end; -} - // if then fi for while until select done done case esac break continue return // Free one pipeline segment. @@ -1489,8 +1497,7 @@ static int parse_line(char *line, struct sh_function *sp) if (*start=='#') while (*start && *start != '\n') ++start; // Parse next word and detect overflow (too many nested quotes). - if ((end = parse_word(start)) == (void *)1) - goto flush; + if ((end = parse_word(start, 0)) == (void *)1) goto flush; // Is this a new pipeline segment? if (!pl) { @@ -1715,7 +1722,7 @@ check: return 0; flush: - if (s) syntax_err("bad %s", s); + if (s) syntax_err(s); free_function(sp); return 0-!!s; @@ -1754,7 +1761,7 @@ static int pipe_segments(char *ctl, int *pipes, int **urd) // Did the previous pipe segment pipe input into us? if (*pipes != -1) { - save_redirect(urd, *pipes, 0); + if (save_redirect(urd, *pipes, 0)) return 1; close(*pipes); *pipes = -1; } @@ -1767,7 +1774,12 @@ static int pipe_segments(char *ctl, int *pipes, int **urd) // TODO check did not reach end of pipeline after loop return 1; } - save_redirect(urd, pipes[1], 1); + if (save_redirect(urd, pipes[1], 1)) { + close(pipes[0]); + close(pipes[1]); + + return 1; + } if (pipes[1] != 1) close(pipes[1]); fcntl(*pipes, F_SETFD, FD_CLOEXEC); if (ctl[1] == '&') save_redirect(urd, 1, 2); @@ -1812,6 +1824,8 @@ static void run_function(struct sh_pipeline *pl) // TODO can't free sh_process delete until ready to dispose else no debug output + TT.hfd = 10; + // iterate through pipeline segments while (pl) { struct sh_arg *arg = pl->arg; @@ -1843,7 +1857,7 @@ if (BUGBUG) dprintf(255, "%d runtype=%d %s %s\n", getpid(), pl->type, s, ctl); i = ss ? atol(ss) : 0; if (i<1) i = 1; if (!blk || arg->c>2 || ss[strspn(ss, "0123456789")]) { - syntax_err("bad %s", s); + syntax_err(s); break; } i = atol(ss); @@ -1924,8 +1938,7 @@ if (BUGBUG) dprintf(255, "%d runtype=%d %s %s\n", getpid(), pl->type, s, ctl); pp = expand_redir(end->arg, 1, blk->urd); blk->urd = pp->urd; if (pp->arg.c) { -// TODO this is a syntax_error - perror_msg("unexpected %s", *pp->arg.v); + syntax_err(*pp->arg.v); llist_traverse(pp->delete, free); free(pp); break; @@ -2129,7 +2142,7 @@ static void setonlylocal(char ***to, char *name, char *val) static void subshell_setup(void) { struct passwd *pw = getpwuid(getuid()); - int to, from, pid = 0, ppid = 0, mypid, myppid, len; + int to, from, pid = 0, ppid = 0, zpid = 0, mypid, myppid, len; // TODO: you can unset readonly and these first 4 aren't malloc() char *s, *ss, **ll, *locals[] = {"GROUPS=", "SECONDS=", "RANDOM=", "LINENO=", xmprintf("PPID=%d", myppid = getppid()), xmprintf("EUID=%d", geteuid()), @@ -2182,6 +2195,7 @@ static void subshell_setup(void) 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; + if (!CFG_TOYBOX_FORK && *s == '$' && s[1] == '=') zpid = atoi(s+2); } environ[toys.optc = to] = 0; @@ -2210,6 +2224,7 @@ static void subshell_setup(void) // sanity check: magic env variable, pipe status if (CFG_TOYBOX_FORK || toys.stacktop || pid!=mypid || ppid!=myppid) return; if (fstat(254, &st) || !S_ISFIFO(st.st_mode)) error_exit(0); + TT.pid = zpid; fcntl(254, F_SETFD, FD_CLOEXEC); fp = fdopen(254, "r"); @@ -2230,9 +2245,9 @@ void sh_main(void) int prompt = 0, ii = FLAG(i); struct sh_arg arg; - TT.hfd = 10; signal(SIGPIPE, SIG_IGN); + TT.pid = getpid(); TT.arg = &arg; if (!(arg.c = toys.optc)) { arg.v = xmalloc(2*sizeof(char *)); @@ -2263,7 +2278,7 @@ if (BUGBUG) { int fd = open("/dev/tty", O_RDWR); dup2(fd, 255); close(fd); } // TODO unify fmemopen() here with sh_run if (cc) f = fmemopen(cc, strlen(cc), "r"); else if (*toys.optargs) { - +// TODO: syntax_err should exit from shell scripts if (!(f = fopen(*toys.optargs, "r"))) { char *pp = getvar("PATH"); struct string_list *sl = find_in_path(pp?pp:_PATH_DEFPATH, *toys.optargs); |