diff options
Diffstat (limited to 'walk.c')
| -rw-r--r-- | walk.c | 97 |
1 files changed, 68 insertions, 29 deletions
@@ -17,6 +17,8 @@ static bool haspreredir(Node *); static bool isallpre(Node *); static bool dofork(bool); static void dopipe(Node *); +static void loop_body(Node* n); +static int if_state = 2; /* last if, for "if not" interactive top-level */ /* Tail-recursive version of walk() */ @@ -32,6 +34,7 @@ top: sigchk(); set(TRUE); return TRUE; } + if (parent && n->type != nIfnot) if_state = 2; switch (n->type) { case nArgs: case nBackq: case nConcat: case nCount: case nFlat: case nLappend: case nRedir: case nVar: @@ -95,58 +98,71 @@ top: sigchk(); true_cmd = true_cmd->u[0].p; } cond = TRUE; - if (!walk(n->u[0].p, TRUE)) - true_cmd = false_cmd; /* run the else clause */ + if_state = walk(n->u[0].p, TRUE); cond = oldcond; - WALK(true_cmd, parent); + WALK(if_state ? true_cmd : false_cmd, parent); + } + case nIfnot: { + if (if_state == 2) + rc_error("`if not' must follow `if'"); + if (if_state == 0) + walk(n->u[0].p, TRUE); + if_state = 2; + break; } case nWhile: { - Jbwrap j; - Edata jbreak; - Estack e1, e2; - bool testtrue, oldcond = cond; + Jbwrap break_jb; + Edata break_data; + Estack break_stack; + bool testtrue; + const bool oldcond = cond; cond = TRUE; if (!walk(n->u[0].p, TRUE)) { /* prevent spurious breaks inside test */ cond = oldcond; break; } cond = oldcond; - if (sigsetjmp(j.j, 1)) + if (sigsetjmp(break_jb.j, 1)) break; - jbreak.jb = &j; - except(eBreak, jbreak, &e1); + break_data.jb = &break_jb; + except(eBreak, break_data, &break_stack); + + cond = oldcond; do { - Edata block; - block.b = newblock(); - except(eArena, block, &e2); - walk(n->u[1].p, TRUE); + Edata iter_data; + Estack iter_stack; + iter_data.b = newblock(); + except(eArena, iter_data, &iter_stack); + loop_body(n->u[1].p); cond = TRUE; testtrue = walk(n->u[0].p, TRUE); cond = oldcond; - unexcept(); /* eArena */ + unexcept(eArena); } while (testtrue); cond = oldcond; - unexcept(); /* eBreak */ + unexcept(eBreak); break; } case nForin: { List *l, *var = glom(n->u[0].p); - Jbwrap j; - Estack e1, e2; - Edata jbreak; - if (sigsetjmp(j.j, 1)) + Jbwrap break_jb; + Edata break_data; + Estack break_stack; + if (sigsetjmp(break_jb.j, 1)) break; - jbreak.jb = &j; - except(eBreak, jbreak, &e1); + break_data.jb = &break_jb; + except(eBreak, break_data, &break_stack); + for (l = listcpy(glob(glom(n->u[1].p)), nalloc); l != NULL; l = l->n) { - Edata block; + Edata iter_data; + Estack iter_stack; assign(var, word(l->w, NULL), FALSE); - block.b = newblock(); - except(eArena, block, &e2); - walk(n->u[2].p, TRUE); - unexcept(); /* eArena */ + iter_data.b = newblock(); + except(eArena, iter_data, &iter_stack); + loop_body(n->u[2].p); + unexcept(eArena); } - unexcept(); /* eBreak */ + unexcept(eBreak); break; } case nSubshell: @@ -240,7 +256,7 @@ top: sigchk(); except(eVarstack, var, &e); walk(n->u[1].p, parent); varrm(v->w, TRUE); - unexcept(); /* eVarstack */ + unexcept(eVarstack); } } else panic("unexpected node in preredir section of walk"); @@ -364,3 +380,26 @@ static void dopipe(Node *n) { setpipestatus(stats, i); sigchk(); } + +/* From http://en.cppreference.com/w/c/program/setjmp + * According to the C standard setjmp() must appear only in the following 4 constructs: + * 1. switch (setjmp(args)) {statements} + * 2. if (setjmp(args) == Const) {statements} with any of + * operators: ==, !=, <, >, <=, >= + * 3. while (! setjmp(args)) {statements} + * 4. setjmp(args); +*/ +static void loop_body(Node* nd) +{ + Node *volatile n = nd; + Jbwrap cont_jb; + Edata cont_data; + Estack cont_stack; + + if (sigsetjmp(cont_jb.j, 1) == 0) { + cont_data.jb = &cont_jb; + except(eContinue, cont_data, &cont_stack); + walk(n, TRUE); + unexcept(eContinue); + } +} |