diff options
Diffstat (limited to 'src/ex_eval.c')
| -rw-r--r-- | src/ex_eval.c | 2004 |
1 files changed, 2004 insertions, 0 deletions
diff --git a/src/ex_eval.c b/src/ex_eval.c new file mode 100644 index 000000000..921d60867 --- /dev/null +++ b/src/ex_eval.c @@ -0,0 +1,2004 @@ +/* vi:set ts=8 sts=4 sw=4: + * + * VIM - Vi IMproved by Bram Moolenaar + * + * Do ":help uganda" in Vim to read copying and usage conditions. + * Do ":help credits" in Vim to see a list of people who contributed. + * See README.txt for an overview of the Vim source code. + */ + +/* + * ex_eval.c: functions for Ex command line for the +eval feature. + */ + +#include "vim.h" + +#if defined(FEAT_EVAL) || defined(PROTO) + +static void free_msglist __ARGS((struct msglist *l)); +static int throw_exception __ARGS((void *, int, char_u *)); +static void rewind_conditionals __ARGS((struct condstack *, + int, int, int *)); + +/* + * Exception handling terms: + * + * :try ":try" command \ + * ... try block | + * :catch RE ":catch" command | + * ... catch clause |- try conditional + * :finally ":finally" command | + * ... finally clause | + * :endtry ":endtry" command / + * + * The try conditional may have any number of catch clauses and at most one + * finally clause. A ":throw" command can be inside the try block, a catch + * clause, the finally clause, or in a function called or script sourced from + * there or even outside the try conditional. Try conditionals may be nested. + */ + +/* + * Configuration whether an exception is thrown on error or interrupt. When + * the preprocessor macros below evaluate to FALSE, an error (did_emsg) or + * interrupt (got_int) under an active try conditional terminates the script + * after the non-active finally clauses of all active try conditionals have been + * executed. Otherwise, errors and/or interrupts are converted into catchable + * exceptions (did_throw additionally set), which terminate the script only if + * not caught. For user exceptions, only did_throw is set. (Note: got_int can + * be set asyncronously afterwards by a SIGINT, so did_throw && got_int is not + * a reliant test that the exception currently being thrown is an interrupt + * exception. Similarly, did_emsg can be set afterwards on an error in an + * (unskipped) conditional command inside an inactive conditional, so did_throw + * && did_emsg is not a reliant test that the exception currently being thrown + * is an error exception.) - The macros can be defined as expressions checking + * for a variable that is allowed to be changed during execution of a script. + */ +#if 0 +/* Expressions used for testing during the development phase. */ +# define THROW_ON_ERROR (!eval_to_number("$VIMNOERRTHROW")) +# define THROW_ON_INTERRUPT (!eval_to_number("$VIMNOINTTHROW")) +# define THROW_TEST +#else +/* Values used for the Vim release. */ +# define THROW_ON_ERROR TRUE +# define THROW_ON_INTERRUPT TRUE +#endif + +static void catch_exception __ARGS((except_T *excp)); +static void finish_exception __ARGS((except_T *excp)); +static void discard_exception __ARGS((except_T *excp, int was_finished)); +static void report_pending __ARGS((int action, int pending, void *value)); + +/* + * When several errors appear in a row, setting "force_abort" is delayed until + * the failing command returned. "cause_abort" is set to TRUE meanwhile, in + * order to indicate that situation. This is useful when "force_abort" was set + * during execution of a function call from an expression: the aborting of the + * expression evaluation is done without producing any error messages, but all + * error messages on parsing errors during the expression evaluation are given + * (even if a try conditional is active). + */ +static int cause_abort = FALSE; + +/* + * Return TRUE when immdediately aborting on error, or when an interrupt + * occurred or an exception was thrown but not caught. Use for ":{range}call" + * to check whether an aborted function that does not handle a range itself + * should be called again for the next line in the range. Also used for + * cancelling expression evaluation after a function call caused an immediate + * abort. Note that the first emsg() call temporarily resets "force_abort" + * until the throw point for error messages has been reached. That is, during + * cancellation of an expression evaluation after an aborting function call or + * due to a parsing error, aborting() always returns the same value. + */ + int +aborting() +{ + return (did_emsg && force_abort) || got_int || did_throw; +} + +/* + * The value of "force_abort" is temporarily reset by the first emsg() call + * during an expression evaluation, and "cause_abort" is used instead. It might + * be necessary to restore "force_abort" even before the throw point for the + * error message has been reached. update_force_abort() should be called then. + */ + void +update_force_abort() +{ + if (cause_abort) + force_abort = TRUE; +} + +/* + * Return TRUE if a command with a subcommand resulting in "retcode" should + * abort the script processing. Can be used to suppress an autocommand after + * execution of a failing subcommand as long as the error message has not been + * displayed and actually caused the abortion. + */ + int +should_abort(retcode) + int retcode; +{ + return ((retcode == FAIL && trylevel != 0 && !emsg_silent) || aborting()); +} + +/* + * Return TRUE if a function with the "abort" flag should not be considered + * ended on an error. This means that parsing commands is continued in order + * to find finally clauses to be executed, and that some errors in skipped + * commands are still reported. + */ + int +aborted_in_try() +{ + /* This function is only called after an error. In this case, "force_abort" + * determines whether searching for finally clauses is necessary. */ + return force_abort; +} + +/* + * cause_errthrow(): Cause a throw of an error exception if appropriate. + * Return TRUE if the error message should not be displayed by emsg(). + * Sets "ignore", if the emsg() call should be ignored completely. + * + * When several messages appear in the same command, the first is usually the + * most specific one and used as the exception value. The "severe" flag can be + * set to TRUE, if a later but severer message should be used instead. + */ + int +cause_errthrow(mesg, severe, ignore) + char_u *mesg; + int severe; + int *ignore; +{ + struct msglist *elem; + struct msglist **plist; + + /* + * Do nothing when displaying the interrupt message or reporting an uncaught + * exception (which has already been discarded then) at the top level. Also + * when no exception can be thrown. The message will be displayed by + * emsg(). + */ + if (suppress_errthrow) + return FALSE; + + /* + * If emsg() has not been called previously, temporarily reset "force_abort" + * until the throw point for error messages has been reached. This ensures + * that aborting() returns the same value for all errors that appear in the + * same command. This means particularly that for parsing errors during + * expression evaluation emsg() will be called multiply, even when the + * expression is evaluated from a finally clause that was activated due to + * an aborting error, interrupt, or exception. + */ + if (!did_emsg) + { + cause_abort = force_abort; + force_abort = FALSE; + } + + /* + * If no try conditional is active and no exception is being thrown and + * there has not been an error in a try conditional or a throw so far, do + * nothing (for compatibility of non-EH scripts). The message will then be + * displayed by emsg(). When ":silent!" was used and we are not currently + * throwing an exception, do nothing. The message text will then be stored + * to v:errmsg by emsg() without displaying it. + */ + if (((trylevel == 0 && !cause_abort) || emsg_silent) && !did_throw) + return FALSE; + + /* + * Ignore an interrupt message when inside a try conditional or when an + * exception is being thrown or when an error in a try conditional or throw + * has been detected previously. This is important in order that an + * interrupt exception is catchable by the innermost try conditional and + * not replaced by an interrupt message error exception. + */ + if (mesg == (char_u *)_(e_interr)) + { + *ignore = TRUE; + return TRUE; + } + + /* + * Ensure that all commands in nested function calls and sourced files + * are aborted immediately. + */ + cause_abort = TRUE; + + /* + * When an exception is being thrown, some commands (like conditionals) are + * not skipped. Errors in those commands may affect what of the subsequent + * commands are regarded part of catch and finally clauses. Catching the + * exception would then cause execution of commands not intended by the + * user, who wouldn't even get aware of the problem. Therefor, discard the + * exception currently being thrown to prevent it from being caught. Just + * execute finally clauses and terminate. + */ + if (did_throw) + { + /* When discarding an interrupt exception, reset got_int to prevent the + * same interrupt being converted to an exception again and discarding + * the error exception we are about to throw here. */ + if (current_exception->type == ET_INTERRUPT) + got_int = FALSE; + discard_current_exception(); + } + +#ifdef THROW_TEST + if (!THROW_ON_ERROR) + { + /* + * Print error message immediately without searching for a matching + * catch clause; just finally clauses are executed before the script + * is terminated. + */ + return FALSE; + } + else +#endif + { + /* + * Prepare the throw of an error exception, so that everything will + * be aborted (except for executing finally clauses), until the error + * exception is caught; if still uncaught at the top level, the error + * message will be displayed and the script processing terminated + * then. - This function has no access to the conditional stack. + * Thus, the actual throw is made after the failing command has + * returned. - Throw only the first of several errors in a row, except + * a severe error is following. + */ + if (msg_list != NULL) + { + plist = msg_list; + while (*plist != NULL) + plist = &(*plist)->next; + + elem = (struct msglist *)alloc((unsigned)sizeof(struct msglist)); + if (elem == NULL) + { + suppress_errthrow = TRUE; + EMSG(_(e_outofmem)); + } + else + { + elem->msg = vim_strsave(mesg); + if (elem->msg == NULL) + { + vim_free(elem); + suppress_errthrow = TRUE; + EMSG(_(e_outofmem)); + } + else + { + elem->next = NULL; + elem->throw_msg = NULL; + *plist = elem; + if (plist == msg_list || severe) + { + char_u *tmsg; + + /* Skip the extra "Vim " prefix for message "E458". */ + tmsg = elem->msg; + if (STRNCMP(tmsg, "Vim E", 5) == 0 + && VIM_ISDIGIT(tmsg[5]) + && VIM_ISDIGIT(tmsg[6]) + && VIM_ISDIGIT(tmsg[7]) + && tmsg[8] == ':' + && tmsg[9] == ' ') + (*msg_list)->throw_msg = &tmsg[4]; + else + (*msg_list)->throw_msg = tmsg; + } + } + } + } + return TRUE; + } +} + +/* + * Free a "msg_list" and the messages it contains. + */ + static void +free_msglist(l) + struct msglist *l; +{ + struct msglist *messages, *next; + + messages = l; + while (messages != NULL) + { + next = messages->next; + vim_free(messages->msg); + vim_free(messages); + messages = next; + } +} + +/* + * Throw the message specified in the call to cause_errthrow() above as an + * error exception. If cstack is NULL, postpone the throw until do_cmdline() + * has returned (see do_one_cmd()). + */ + void +do_errthrow(cstack, cmdname) + struct condstack *cstack; + char_u *cmdname; +{ + /* + * Ensure that all commands in nested function calls and sourced files + * are aborted immediately. + */ + if (cause_abort) + { + cause_abort = FALSE; + force_abort = TRUE; + } + + /* If no exception is to be thrown or the conversion should be done after + * returning to a previous invocation of do_one_cmd(), do nothing. */ + if (*msg_list == NULL) + return; + + if (throw_exception(*msg_list, ET_ERROR, cmdname) == FAIL) + free_msglist(*msg_list); + else + { + if (cstack != NULL) + do_throw(cstack); + else + need_rethrow = TRUE; + } + *msg_list = NULL; +} + +/* + * do_intthrow(): Replace the current exception by an interrupt or interrupt + * exception if appropriate. Return TRUE if the current exception is discarded, + * FALSE otherwise. + */ + int +do_intthrow(cstack) + struct condstack *cstack; +{ + /* + * If no interrupt occurred or no try conditional is active and no exception + * is being thrown, do nothing (for compatibility of non-EH scripts). + */ + if (!got_int || (trylevel == 0 && !did_throw)) + return FALSE; + +#ifdef THROW_TEST /* avoid warning for condition always true */ + if (!THROW_ON_INTERRUPT) + { + /* + * The interrupt aborts everything except for executing finally clauses. + * Discard any user or error or interrupt exception currently being + * thrown. + */ + if (did_throw) + discard_current_exception(); + } + else +#endif + { + /* + * Throw an interrupt exception, so that everything will be aborted + * (except for executing finally clauses), until the interrupt exception + * is caught; if still uncaught at the top level, the script processing + * will be terminated then. - If an interrupt exception is already + * being thrown, do nothing. + * + */ + if (did_throw) + { + if (current_exception->type == ET_INTERRUPT) + return FALSE; + + /* An interrupt exception replaces any user or error exception. */ + discard_current_exception(); + } + if (throw_exception("Vim:Interrupt", ET_INTERRUPT, NULL) != FAIL) + do_throw(cstack); + } + + return TRUE; +} + + +/* + * Throw a new exception. Return FAIL when out of memory or it was tried to + * throw an illegal user exception. "value" is the exception string for a user + * or interrupt exception, or points to a message list in case of an error + * exception. + */ + static int +throw_exception(value, type, cmdname) + void *value; + int type; + char_u *cmdname; +{ + except_T *excp; + char_u *p, *mesg, *val; + int cmdlen; + + /* + * Disallow faking Interrupt or error exceptions as user exceptions. They + * would be treated differently from real interrupt or error exceptions when + * no active try block is found, see do_cmdline(). + */ + if (type == ET_USER) + { + if (STRNCMP((char_u *)value, "Vim", 3) == 0 && + (((char_u *)value)[3] == NUL || ((char_u *)value)[3] == ':' || + ((char_u *)value)[3] == '(')) + { + EMSG(_("E608: Cannot :throw exceptions with 'Vim' prefix")); + goto fail; + } + } + + excp = (except_T *)alloc((unsigned)sizeof(except_T)); + if (excp == NULL) + goto nomem; + + if (type == ET_ERROR) + { + /* Store the original message and prefix the exception value with + * "Vim:" or, if a command name is given, "Vim(cmdname):". */ + excp->messages = (struct msglist *)value; + mesg = excp->messages->throw_msg; + if (cmdname != NULL && *cmdname != NUL) + { + cmdlen = STRLEN(cmdname); + excp->value = vim_strnsave((char_u *)"Vim(", + 4 + cmdlen + 2 + (int)STRLEN(mesg)); + if (excp->value == NULL) + goto nomem; + STRCPY(&excp->value[4], cmdname); + STRCPY(&excp->value[4 + cmdlen], "):"); + val = excp->value + 4 + cmdlen + 2; + } + else + { + excp->value = vim_strnsave((char_u *)"Vim:", 4 + (int)STRLEN(mesg)); + if (excp->value == NULL) + goto nomem; + val = excp->value + 4; + } + + /* msg_add_fname may have been used to prefix the message with a file + * name in quotes. In the exception value, put the file name in + * parentheses and move it to the end. */ + for (p = mesg; ; p++) + { + if (*p == NUL + || (*p == 'E' + && VIM_ISDIGIT(p[1]) + && (p[2] == ':' + || (VIM_ISDIGIT(p[2]) + && (p[3] == ':' + || (VIM_ISDIGIT(p[3]) + && p[4] == ':')))))) + { + if (*p == NUL || p == mesg) /* 'E123' missing or at beginning */ + STRCAT(val, mesg); + else + { + /* '"filename" E123: message text' */ + if (mesg[0] != '"' || p-2 < &mesg[1] || + p[-2] != '"' || p[-1] != ' ') + /* "E123:" is part of the file name. */ + continue; + + STRCAT(val, p); + p[-2] = NUL; + sprintf((char *)(val + STRLEN(p)), " (%s)", &mesg[1]); + p[-2] = '"'; + } + break; + } + } + } + else + excp->value = value; + + excp->type = type; + excp->throw_name = vim_strsave(sourcing_name == NULL + ? (char_u *)"" : sourcing_name); + if (excp->throw_name == NULL) + { + if (type == ET_ERROR) + vim_free(excp->value); + goto nomem; + } + excp->throw_lnum = sourcing_lnum; + + if (p_verbose >= 13 || debug_break_level > 0) + { + int save_msg_silent = msg_silent; + + if (debug_break_level > 0) + msg_silent = FALSE; /* display messages */ + ++no_wait_return; + msg_scroll = TRUE; /* always scroll up, don't overwrite */ + msg_str((char_u *)_("Exception thrown: %s"), excp->value); + msg_puts((char_u *)"\n"); /* don't overwrite this either */ + cmdline_row = msg_row; + --no_wait_return; + if (debug_break_level > 0) + msg_silent = save_msg_silent; + } + + current_exception = excp; + return OK; + +nomem: + vim_free(excp); + suppress_errthrow = TRUE; + EMSG(_(e_outofmem)); +fail: + current_exception = NULL; + return FAIL; +} + +/* + * Discard an exception. "was_finished" is set when the exception has been + * caught and the catch clause has been ended normally. + */ + static void +discard_exception(excp, was_finished) + except_T *excp; + int was_finished; +{ + char_u *saved_IObuff; + + if (excp == NULL) + { + EMSG(_(e_internal)); + return; + } + + if (p_verbose >= 13 || debug_break_level > 0) + { + int save_msg_silent = msg_silent; + + saved_IObuff = vim_strsave(IObuff); + if (debug_break_level > 0) + msg_silent = FALSE; /* display messages */ + ++no_wait_return; + msg_scroll = TRUE; /* always scroll up, don't overwrite */ + msg_str(was_finished + ? (char_u *)_("Exception finished: %s") + : (char_u *)_("Exception discarded: %s"), + excp->value); + msg_puts((char_u *)"\n"); /* don't overwrite this either */ + cmdline_row = msg_row; + --no_wait_return; + if (debug_break_level > 0) + msg_silent = save_msg_silent; + STRCPY(IObuff, saved_IObuff); + vim_free(saved_IObuff); + } + if (excp->type != ET_INTERRUPT) + vim_free(excp->value); + if (excp->type == ET_ERROR) + free_msglist(excp->messages); + vim_free(excp->throw_name); + vim_free(excp); +} + +/* + * Discard the exception currently being thrown. + */ + void +discard_current_exception() +{ + discard_exception(current_exception, FALSE); + current_exception = NULL; + did_throw = FALSE; + need_rethrow = FALSE; +} + +/* + * Put an exception on the caught stack. + */ + static void +catch_exception(excp) + except_T *excp; +{ + excp->caught = caught_stack; + caught_stack = excp; + set_vim_var_string(VV_EXCEPTION, excp->value, -1); + if (*excp->throw_name != NUL) + { + if (excp->throw_lnum != 0) + sprintf((char *)IObuff, _("%s, line %ld"), excp->throw_name, + (long)excp->throw_lnum); + else + STRCPY(IObuff, excp->throw_name); + set_vim_var_string(VV_THROWPOINT, IObuff, -1); + } + else + /* throw_name not set on an exception from a command that was typed. */ + set_vim_var_string(VV_THROWPOINT, NULL, -1); + + if (p_verbose >= 13 || debug_break_level > 0) + { + int save_msg_silent = msg_silent; + + if (debug_break_level > 0) + msg_silent = FALSE; /* display messages */ + ++no_wait_return; + msg_scroll = TRUE; /* always scroll up, don't overwrite */ + msg_str((char_u *)_("Exception caught: %s"), excp->value); + msg_puts((char_u *)"\n"); /* don't overwrite this either */ + cmdline_row = msg_row; + --no_wait_return; + if (debug_break_level > 0) + msg_silent = save_msg_silent; + } +} + +/* + * Remove an exception from the caught stack. + */ + static void +finish_exception(excp) + except_T *excp; +{ + if (excp != caught_stack) + EMSG(_(e_internal)); + caught_stack = caught_stack->caught; + if (caught_stack != NULL) + { + set_vim_var_string(VV_EXCEPTION, caught_stack->value, -1); + if (*caught_stack->throw_name != NUL) + { + if (caught_stack->throw_lnum != 0) + sprintf((char *)IObuff, + _("%s, line %ld"), caught_stack->throw_name, + (long)caught_stack->throw_lnum); + else + STRCPY(IObuff, caught_stack->throw_name); + set_vim_var_string(VV_THROWPOINT, IObuff, -1); + } + else + /* throw_name not set on an exception from a command that was + * typed. */ + set_vim_var_string(VV_THROWPOINT, NULL, -1); + } + else + { + set_vim_var_string(VV_EXCEPTION, NULL, -1); + set_vim_var_string(VV_THROWPOINT, NULL, -1); + } + + /* Discard the exception, but use the finish message for 'verbose'. */ + discard_exception(excp, TRUE); +} + +/* + * Flags specifying the message displayed by report_pending. + */ +#define RP_MAKE 0 +#define RP_RESUME 1 +#define RP_DISCARD 2 + +/* + * Report information about something pending in a finally clause if required by + * the 'verbose' option or when debugging. "action" tells whether something is + * made pending or something pending is resumed or discarded. "pending" tells + * what is pending. "value" specifies the return value for a pending ":return" + * or the exception value for a pending exception. + */ + static void +report_pending(action, pending, value) + int action; + int pending; + void *value; +{ + char_u *mesg; + char *s; + int save_msg_silent; + + + switch (action) + { + case RP_MAKE: + mesg = (char_u *)_("%s made pending"); + break; + case RP_RESUME: + mesg = (char_u *)_("%s resumed"); + break; + /* case RP_DISCARD: */ + default: + mesg = (char_u *)_("%s discarded"); + break; + } + + switch (pending) + { + case CSTP_NONE: + return; + + case CSTP_CONTINUE: + s = ":continue"; + break; + case CSTP_BREAK: + s = ":break"; + break; + case CSTP_FINISH: + s = ":finish"; + break; + case CSTP_RETURN: + /* ":return" command producing value, allocated */ + s = (char *)get_return_cmd(value); + break; + + default: + if (pending & CSTP_THROW) + { + sprintf((char *)IObuff, (char *)mesg, _("Exception")); + mesg = vim_strnsave(IObuff, (int)STRLEN(IObuff) + 4); + STRCAT(mesg, ": %s"); + s = (char *)((except_T *)value)->value; + } + else if ((pending & CSTP_ERROR) && (pending & CSTP_INTERRUPT)) + s = _("Error and interrupt"); + else if (pending & CSTP_ERROR) + s = _("Error"); + else /* if (pending & CSTP_INTERRUPT) */ + s = _("Interrupt"); + } + + save_msg_silent = msg_silent; + if (debug_break_level > 0) + msg_silent = FALSE; /* display messages */ + ++no_wait_return; + msg_scroll = TRUE; /* always scroll up, don't overwrite */ + msg_str(mesg, (char_u *)s); + msg_puts((char_u *)"\n"); /* don't overwrite this either */ + cmdline_row = msg_row; + --no_wait_return; + if (debug_break_level > 0) + msg_silent = save_msg_silent; + + if (pending == CSTP_RETURN) + vim_free(s); + else if (pending & CSTP_THROW) + vim_free(mesg); +} + +/* + * If something is made pending in a finally clause, report it if required by + * the 'verbose' option or when debugging. + */ + void +report_make_pending(pending, value) + int pending; + void *value; +{ + if (p_verbose >= 14 || debug_break_level > 0) + report_pending(RP_MAKE, pending, value); +} + +/* + * If something pending in a finally clause is resumed at the ":endtry", report + * it if required by the 'verbose' option or when debugging. + */ + void +report_resume_pending(pending, value) + int pending; + void *value; +{ + if (p_verbose >= 14 || debug_break_level > 0) + report_pending(RP_RESUME, pending, value); +} + +/* + * If something pending in a finally clause is discarded, report it if required + * by the 'verbose' option or when debugging. + */ + void +report_discard_pending(pending, value) + int pending; + void *value; +{ + if (p_verbose >= 14 || debug_break_level > 0) + report_pending(RP_DISCARD, pending, value); +} + + +/* + * ":if". + */ + void +ex_if(eap) + exarg_T *eap; +{ + int error; + int skip; + int result; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_idx == CSTACK_LEN - 1) + eap->errmsg = (char_u *)N_("E579: :if nesting too deep"); + else + { + ++cstack->cs_idx; + cstack->cs_flags[cstack->cs_idx] = 0; + + /* + * Don't do something after an error, interrupt, or throw, or when there + * is a surrounding conditional and it was not active. + */ + skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0 + && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE)); + + result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip); + + if (!skip && !error) + { + if (result) + cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE; + } + else + /* set TRUE, so this conditional will never get active */ + cstack->cs_flags[cstack->cs_idx] = CSF_TRUE; + } +} + +/* + * ":endif". + */ + void +ex_endif(eap) + exarg_T *eap; +{ + did_endif = TRUE; + if (eap->cstack->cs_idx < 0 + || (eap->cstack->cs_flags[eap->cstack->cs_idx] & + (CSF_WHILE | CSF_TRY))) + eap->errmsg = (char_u *)N_("E580: :endif without :if"); + else + { + /* + * When debugging or a breakpoint was encountered, display the debug + * prompt (if not already done). This shows the user that an ":endif" + * is executed when the ":if" or a previous ":elseif" was not TRUE. + * Handle a ">quit" debug command as if an interrupt had occurred before + * the ":endif". That is, throw an interrupt exception if appropriate. + * Doing this here prevents an exception for a parsing error being + * discarded by throwing the interrupt exception later on. + */ + if (!(eap->cstack->cs_flags[eap->cstack->cs_idx] & CSF_TRUE) && + dbg_check_skipped(eap)) + (void)do_intthrow(eap->cstack); + + --eap->cstack->cs_idx; + } +} + +/* + * ":else" and ":elseif". + */ + void +ex_else(eap) + exarg_T *eap; +{ + int error; + int skip; + int result; + struct condstack *cstack = eap->cstack; + + /* + * Don't do something after an error, interrupt, or throw, or when there is + * a surrounding conditional and it was not active. + */ + skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0 + && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE)); + + if (cstack->cs_idx < 0 + || (cstack->cs_flags[cstack->cs_idx] & (CSF_WHILE | CSF_TRY))) + { + if (eap->cmdidx == CMD_else) + { + eap->errmsg = (char_u *)N_("E581: :else without :if"); + return; + } + eap->errmsg = (char_u *)N_("E582: :elseif without :if"); + skip = TRUE; + } + else if (cstack->cs_flags[cstack->cs_idx] & CSF_ELSE) + { + if (eap->cmdidx == CMD_else) + { + eap->errmsg = (char_u *)N_("E583: multiple :else"); + return; + } + eap->errmsg = (char_u *)N_("E584: :elseif after :else"); + skip = TRUE; + } + + /* if skipping or the ":if" was TRUE, reset ACTIVE, otherwise set it */ + if (skip || cstack->cs_flags[cstack->cs_idx] & CSF_TRUE) + { + if (eap->errmsg == NULL) + cstack->cs_flags[cstack->cs_idx] = CSF_TRUE; + skip = TRUE; /* don't evaluate an ":elseif" */ + } + else + cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE; + + /* + * When debugging or a breakpoint was encountered, display the debug prompt + * (if not already done). This shows the user that an ":else" or ":elseif" + * is executed when the ":if" or previous ":elseif" was not TRUE. Handle + * a ">quit" debug command as if an interrupt had occurred before the + * ":else" or ":elseif". That is, set "skip" and throw an interrupt + * exception if appropriate. Doing this here prevents that an exception + * for a parsing errors is discarded when throwing the interrupt exception + * later on. + */ + if (!skip && dbg_check_skipped(eap) && got_int) + { + (void)do_intthrow(cstack); + skip = TRUE; + } + + if (eap->cmdidx == CMD_elseif) + { + result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip); + /* When throwing error exceptions, we want to throw always the first + * of several errors in a row. This is what actually happens when + * a conditional error was detected above and there is another failure + * when parsing the expression. Since the skip flag is set in this + * case, the parsing error will be ignored by emsg(). */ + + if (!skip && !error) + { + if (result) + cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE; + else + cstack->cs_flags[cstack->cs_idx] = 0; + } + else if (eap->errmsg == NULL) + /* set TRUE, so this conditional will never get active */ + cstack->cs_flags[cstack->cs_idx] = CSF_TRUE; + } + else + cstack->cs_flags[cstack->cs_idx] |= CSF_ELSE; +} + +/* + * Handle ":while". + */ + void +ex_while(eap) + exarg_T *eap; +{ + int error; + int skip; + int result; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_idx == CSTACK_LEN - 1) + eap->errmsg = (char_u *)N_("E585: :while nesting too deep"); + else + { + /* + * cs_had_while is set when we have jumped back from the matching + * ":endwhile". When not set, need to initialise this cstack entry. + */ + if (!cstack->cs_had_while) + { + ++cstack->cs_idx; + ++cstack->cs_whilelevel; + cstack->cs_line[cstack->cs_idx] = -1; + } + cstack->cs_flags[cstack->cs_idx] = CSF_WHILE; + + /* + * Don't do something after an error, interrupt, or throw, or when there + * is a surrounding conditional and it was not active. + */ + skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0 + && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE)); + result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip); + + /* + * If this cstack entry was just initialised and is active, set + * cs_had_while flag, so do_cmdline() will set the line number + * in cs_line[]. + */ + if (!skip && !error && result) + { + cstack->cs_flags[cstack->cs_idx] |= CSF_ACTIVE | CSF_TRUE; + cstack->cs_had_while = !cstack->cs_had_while; + } + else + { + cstack->cs_had_while = FALSE; + /* If the ":while" evaluates to FALSE, show the debug prompt at the + * ":endwhile" as if there was a ":break" in a ":while" evaluating + * to TRUE. */ + if (!skip && !error) + cstack->cs_flags[cstack->cs_idx] |= CSF_TRUE; + } + } +} + +/* + * ":continue" + */ + void +ex_continue(eap) + exarg_T *eap; +{ + int idx; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0) + eap->errmsg = (char_u *)N_("E586: :continue without :while"); + else + { + /* Try to find the matching ":while". This might stop at a try + * conditional not in its finally clause (which is then to be executed + * next). Therefor, inactivate all conditionals except the ":while" + * itself (if reached). */ + idx = cleanup_conditionals(cstack, CSF_WHILE, FALSE); + if ((cstack->cs_flags[idx] & CSF_WHILE)) + { + if (cstack->cs_idx > idx) + rewind_conditionals(cstack, idx, CSF_TRY, &cstack->cs_trylevel); + + /* + * Set cs_had_continue, so do_cmdline() will jump back to the + * matching ":while". + */ + cstack->cs_had_continue = TRUE; /* let do_cmdline() handle it */ + } + else + { + /* If a try conditional not in its finally clause is reached first, + * make the ":continue" pending for execution at the ":endtry". */ + cstack->cs_pending[idx] = CSTP_CONTINUE; + report_make_pending(CSTP_CONTINUE, NULL); + } + } +} + +/* + * ":break" + */ + void +ex_break(eap) + exarg_T *eap; +{ + int idx; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0) + eap->errmsg = (char_u *)N_("E587: :break without :while"); + else + { + /* Inactivate conditionals until the matching ":while" or a try + * conditional not in its finally clause (which is then to be + * executed next) is found. In the latter case, make the ":break" + * pending for execution at the ":endtry". */ + idx = cleanup_conditionals(cstack, CSF_WHILE, TRUE); + if (!(cstack->cs_flags[idx] & CSF_WHILE)) + { + cstack->cs_pending[idx] = CSTP_BREAK; + report_make_pending(CSTP_BREAK, NULL); + } + } +} + +/* + * ":endwhile" + */ + void +ex_endwhile(eap) + exarg_T *eap; +{ + struct condstack *cstack = eap->cstack; + int idx; + + if (cstack->cs_whilelevel <= 0 || cstack->cs_idx < 0) + eap->errmsg = e_while; + else + { + if (!(cstack->cs_flags[cstack->cs_idx] & CSF_WHILE)) + { + /* Try to find the matching ":while" and report what's missing. */ + if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY)) + eap->errmsg = e_endif; + else if (cstack->cs_flags[cstack->cs_idx] & CSF_FINALLY) + eap->errmsg = e_endtry; + for (idx = cstack->cs_idx; idx > 0; --idx) + { + if ((cstack->cs_flags[idx] & CSF_TRY) + && !(cstack->cs_flags[idx] & CSF_FINALLY)) + { + /* Give up at a try conditional not in its finally clause. + * Ignore the ":endwhile". */ + eap->errmsg = e_while; + return; + } + if (cstack->cs_flags[idx] & CSF_WHILE) + break; + } + /* Cleanup and rewind all contained (and unclosed) conditionals. */ + (void)cleanup_conditionals(cstack, CSF_WHILE, FALSE); + rewind_conditionals(cstack, idx, CSF_TRY, &cstack->cs_trylevel); + } + + /* + * When debugging or a breakpoint was encountered, display the debug + * prompt (if not already done). This shows the user that an + * ":enwhile" is executed when the ":while" was not TRUE or after + * a ":break". Handle a ">quit" debug command as if an interrupt + * had occurred before the ":endwhile". That is, throw an interrupt + * exception if appropriate. Doing this here prevents that an + * exception for a parsing error is discarded when throwing the + * interrupt exception later on. + */ + else if (cstack->cs_flags[cstack->cs_idx] & CSF_TRUE + && !(cstack->cs_flags[cstack->cs_idx] & CSF_ACTIVE) + && dbg_check_skipped(eap)) + (void)do_intthrow(cstack); + + /* + * Set cs_had_endwhile, so do_cmdline() will jump back to the matching + * ":while". + */ + cstack->cs_had_endwhile = TRUE; + } +} + + +/* + * ":throw expr" + */ + void +ex_throw(eap) + exarg_T *eap; +{ + char_u *arg = eap->arg; + char_u *value; + + if (*arg != NUL && *arg != '|' && *arg != '\n') + value = eval_to_string_skip(arg, &eap->nextcmd, eap->skip); + else + { + EMSG(_(e_argreq)); + value = NULL; + } + + /* On error or when an exception is thrown during argument evaluation, do + * not throw. */ + if (!eap->skip && value != NULL) + { + if (throw_exception(value, ET_USER, NULL) == FAIL) + vim_free(value); + else + do_throw(eap->cstack); + } +} + +/* + * Throw the current exception through the specified cstack. Common routine for + * ":throw" (user exception) and error and interrupt exceptions. Also used for + * rethrowing an uncaught exception. + */ + void +do_throw(cstack) + struct condstack *cstack; +{ + int idx; + int inactivate_try = FALSE; + + /* + * Cleanup and inactivate up to the next surrounding try conditional that + * is not in its finally clause. Normally, do not inactivate the try + * conditional itself, so that its ACTIVE flag can be tested below. But + * if a previous error or interrupt has not been converted to an exception, + * inactivate the try conditional, too, as if the conversion had been done, + * and reset the did_emsg or got_int flag, so this won't happen again at the + * next surrounding try conditional. + */ + if (did_emsg && !THROW_ON_ERROR) + { + inactivate_try = TRUE; + did_emsg = FALSE; + } + if (got_int && !THROW_ON_INTERRUPT) + { + inactivate_try = TRUE; + got_int = FALSE; + } + idx = cleanup_conditionals(cstack, 0, inactivate_try); + if (idx >= 0) + { + /* + * If this try conditional is active and we are before its first + * ":catch", set THROWN so that the ":catch" commands will check whether + * the exception matches. When the exception came from any of the + * catch clauses, it will be made pending at the ":finally" (if present) + * and rethrown at the ":endtry". This will also happen if the try + * conditional is inactive. This is the case when we are throwing an + * exception due to an error or interrupt on the way from a preceding + * ":continue", ":break", ":return", ":finish", error or interrupt (not + * converted to an exception) to the finally clause or from a preceding + * throw of a user or error or interrupt exception to the matching catch + * clause or the finally clause. + */ + if (!(cstack->cs_flags[idx] & CSF_CAUGHT)) + { + if (cstack->cs_flags[idx] & CSF_ACTIVE) + cstack->cs_flags[idx] |= CSF_THROWN; + else + /* THROWN may have already been set for a catchable exception + * that has been discarded. Ensure it is reset for the new + * exception. */ + cstack->cs_flags[idx] &= ~CSF_THROWN; + } + cstack->cs_flags[idx] &= ~CSF_ACTIVE; + cstack->cs_exception[idx] = current_exception; + } +#if 0 + /* TODO: Add optimization below. Not yet done because of interface problems + * to eval.c and ex_cmds2.c. (Servatius) */ + else + { + /* + * There are no catch clauses to check or finally clauses to execute. + * End the current script or function. The exception will be rethrown + * in the caller. + */ + if (getline_equal(eap->getline, eap->cookie, get_func_line)) + current_funccal->returned = TRUE; + elseif (eap->get_func_line == getsourceline) + ((struct source_cookie *)eap->cookie)->finished = TRUE; + } +#endif + + did_throw = TRUE; +} + +/* + * ":try" + */ + void +ex_try(eap) + exarg_T *eap; +{ + int skip; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_idx == CSTACK_LEN - 1) + eap->errmsg = (char_u *)N_("E601: :try nesting too deep"); + else + { + ++cstack->cs_idx; + ++cstack->cs_trylevel; + cstack->cs_flags[cstack->cs_idx] = CSF_TRY; + cstack->cs_pending[cstack->cs_idx] = CSTP_NONE; + + /* + * Don't do something after an error, interrupt, or throw, or when there + * is a surrounding conditional and it was not active. + */ + skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0 + && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE)); + + if (!skip) + { + /* Set ACTIVE and TRUE. TRUE means that the corresponding ":catch" + * commands should check for a match if an exception is thrown and + * that the finally clause needs to be executed. */ + cstack->cs_flags[cstack->cs_idx] |= CSF_ACTIVE | CSF_TRUE; + + /* + * ":silent!", even when used in a try conditional, disables + * displaying of error messages and conversion of errors to + * exceptions. When the silent commands again open a try + * conditional, save "emsg_silent" and reset it so that errors are + * again converted to exceptions. The value is restored when that + * try conditional is left. If it is left normally, the commands + * following the ":endtry" are again silent. If it is left by + * a ":continue", ":break", ":return", or ":finish", the commands + * executed next are again silent. If it is left due to an + * aborting error, an interrupt, or an exception, restoring + * "emsg_silent" does not matter since we are already in the + * aborting state and/or the exception has already been thrown. + * The effect is then just freeing the memory that was allocated + * to save the value. + */ + if (emsg_silent) + { + eslist_T *elem; + + elem = (eslist_T *)alloc((unsigned)sizeof(struct eslist_elem)); + if (elem == NULL) + EMSG(_(e_outofmem)); + else + { + elem->saved_emsg_silent = emsg_silent; + elem->next = cstack->cs_emsg_silent_list; + cstack->cs_emsg_silent_list = elem; + cstack->cs_flags[cstack->cs_idx] |= CSF_SILENT; + emsg_silent = 0; + } + } + } + + } +} + +/* + * ":catch /{pattern}/" and ":catch" + */ + void +ex_catch(eap) + exarg_T *eap; +{ + int idx = 0; + int give_up = FALSE; + int skip = FALSE; + int caught = FALSE; + char_u *end; + int save_char = 0; + char_u *save_cpo; + regmatch_T regmatch; + int prev_got_int; + struct condstack *cstack = eap->cstack; + char_u *pat; + + if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0) + { + eap->errmsg = (char_u *)N_("E603: :catch without :try"); + give_up = TRUE; + } + else + { + if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY)) + { + /* Report what's missing if the matching ":try" is not in its + * finally clause. */ + if (cstack->cs_flags[cstack->cs_idx] & CSF_WHILE) + eap->errmsg = e_endwhile; + else + eap->errmsg = e_endif; + skip = TRUE; + } + for (idx = cstack->cs_idx; idx > 0; --idx) + if (cstack->cs_flags[idx] & CSF_TRY) + break; + if (cstack->cs_flags[idx] & CSF_FINALLY) + { + /* Give up for a ":catch" after ":finally" and ignore it. + * Just parse. */ + eap->errmsg = (char_u *)N_("E604: :catch after :finally"); + give_up = TRUE; + } + else if (cstack->cs_idx > idx) + rewind_conditionals(cstack, idx, CSF_WHILE, &cstack->cs_whilelevel); + } + + if (ends_excmd(*eap->arg)) /* no argument, catch all errors */ + { + pat = (char_u *)".*"; + end = NULL; + eap->nextcmd = find_nextcmd(eap->arg); + } + else + { + pat = eap->arg + 1; + end = skip_regexp(pat, *eap->arg, TRUE, NULL); + } + + if (!give_up) + { + /* + * Don't do something when no exception has been thrown or when the + * corresponding try block never got active (because of an inactive + * surrounding conditional or after an error or interrupt or throw). + */ + if (!did_throw || !(cstack->cs_flags[idx] & CSF_TRUE)) + skip = TRUE; + + /* + * Check for a match only if an exception is thrown but not caught by + * a previous ":catch". An exception that has replaced a discarded + * exception is not checked (THROWN is not set then). + */ + if (!skip && (cstack->cs_flags[idx] & CSF_THROWN) + && !(cstack->cs_flags[idx] & CSF_CAUGHT)) + { + if (end != NULL && *end != NUL && !ends_excmd(*skipwhite(end + 1))) + { + EMSG(_(e_trailing)); + return; + } + + /* When debugging or a breakpoint was encountered, display the + * debug prompt (if not already done) before checking for a match. + * This is a helpful hint for the user when the regular expression + * matching fails. Handle a ">quit" debug command as if an + * interrupt had occurred before the ":catch". That is, discard + * the original exception, replace it by an interrupt exception, + * and don't catch it in this try block. */ + if (!dbg_check_skipped(eap) || !do_intthrow(cstack)) + { + /* Terminate the pattern and avoid the 'l' flag in 'cpoptions' + * while compiling it. */ + if (end != NULL) + { + save_char = *end; + *end = NUL; + } + save_cpo = p_cpo; + p_cpo = (char_u *)""; + regmatch.regprog = vim_regcomp(pat, TRUE); + regmatch.rm_ic = FALSE; + if (end != NULL) + *end = save_char; + p_cpo = save_cpo; + if (regmatch.regprog == NULL) + EMSG2(_(e_invarg2), pat); + else + { + /* + * Save the value of got_int and reset it. We don't want + * a previous interruption cancel matching, only hitting + * CTRL-C while matching should abort it. + */ + prev_got_int = got_int; + got_int = FALSE; + caught = vim_regexec_nl(®match, current_exception->value, + (colnr_T)0); + got_int |= prev_got_int; + vim_free(regmatch.regprog); + } + } + } + + if (caught) + { + /* Make this ":catch" clause active and reset did_emsg, got_int, + * and did_throw. Put the exception on the caught stack. */ + cstack->cs_flags[idx] |= CSF_ACTIVE | CSF_CAUGHT; + did_emsg = got_int = did_throw = FALSE; + catch_exception((except_T *)cstack->cs_exception[idx]); + /* It's mandatory that the current exception is stored in the cstack + * so that it can be discarded at the next ":catch", ":finally", or + * ":endtry" or when the catch clause is left by a ":continue", + * ":break", ":return", ":finish", error, interrupt, or another + * exception. */ + if (cstack->cs_exception[cstack->cs_idx] != current_exception) + EMSG(_(e_internal)); + } + else + { + /* + * If there is a preceding catch clause and it caught the exception, + * finish the exception now. This happens also after errors except + * when this ":catch" was after the ":finally" or not within + * a ":try". Make the try conditional inactive so that the + * following catch clauses are skipped. On an error or interrupt + * after the preceding try block or catch clause was left by + * a ":continue", ":break", ":return", or ":finish", discard the + * pending action. + */ + cleanup_conditionals(cstack, CSF_TRY, TRUE); + } + } + + if (end != NULL) + eap->nextcmd = find_nextcmd(end); +} + +/* + * ":finally" + */ + void +ex_finally(eap) + exarg_T *eap; +{ + int idx; + int skip = FALSE; + int pending = CSTP_NONE; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0) + eap->errmsg = (char_u *)N_("E606: :finally without :try"); + else + { + if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY)) + { + /* Find the matching ":try" and report what's missing. */ + if (cstack->cs_flags[cstack->cs_idx] & CSF_WHILE) + eap->errmsg = e_endwhile; + else + eap->errmsg = e_endif; + for (idx = cstack->cs_idx - 1; idx > 0; --idx) + if (cstack->cs_flags[idx] & CSF_TRY) + break; + /* Make this error pending, so that the commands in the following + * finally clause can be executed. This overrules also a pending + * ":continue", ":break", ":return", or ":finish". */ + pending = CSTP_ERROR; + } + else + idx = cstack->cs_idx; + + if (cstack->cs_flags[idx] & CSF_FINALLY) + { + /* Give up for a multiple ":finally" and ignore it. */ + eap->errmsg = (char_u *)N_("E607: multiple :finally"); + return; + } + if (cstack->cs_idx > idx) + rewind_conditionals(cstack, idx, CSF_WHILE, &cstack->cs_whilelevel); + + /* + * Don't do something when the corresponding try block never got active + * (because of an inactive surrounding conditional or after an error or + * interrupt or throw) or for a ":finally" without ":try" or a multiple + * ":finally". After every other error (did_emsg or the conditional + * errors detected above) or after an interrupt (got_int) or an + * exception (did_throw), the finally clause must be executed. + */ + skip = !(cstack->cs_flags[cstack->cs_idx] & CSF_TRUE); + + if (!skip) + { + /* When debugging or a breakpoint was encountered, display the + * debug prompt (if not already done). The user then knows that the + * finally clause is executed. */ + if (dbg_check_skipped(eap)) + { + /* Handle a ">quit" debug command as if an interrupt had + * occurred before the ":finally". That is, discard the + * original exception and replace it by an interrupt + * exception. */ + (void)do_intthrow(cstack); + } + + /* + * If there is a preceding catch clause and it caught the exception, + * finish the exception now. This happens also after errors except + * when this is a multiple ":finally" or one not within a ":try". + * After an error or interrupt, this also discards a pending + * ":continue", ":break", ":finish", or ":return" from the preceding + * try block or catch clause. + */ + cleanup_conditionals(cstack, CSF_TRY, FALSE); + + /* + * Make did_emsg, got_int, did_throw pending. If set, they overrule + * a pending ":continue", ":break", ":return", or ":finish". Then + * we have particularly to discard a pending return value (as done + * by the call to cleanup_conditionals() above when did_emsg or + * got_int is set). The pending values are restored by the + * ":endtry", except if there is a new error, interrupt, exception, + * ":continue", ":break", ":return", or ":finish" in the following + * finally clause. A missing ":endwhile" or ":endif" detected here + * is treated as if did_emsg and did_throw had already been set, + * respectively in case that the error is not converted to an + * exception, did_throw had already been unset. We must not set + * did_emsg here since that would suppress the error message. + */ + if (pending == CSTP_ERROR || did_emsg || got_int || did_throw) + { + if (cstack->cs_pending[cstack->cs_idx] == CSTP_RETURN) + { + report_discard_pending(CSTP_RETURN, + cstack->cs_retvar[cstack->cs_idx]); + discard_pending_return(cstack->cs_retvar[cstack->cs_idx]); + } + if (pending == CSTP_ERROR && !did_emsg) + pending |= (THROW_ON_ERROR) ? CSTP_THROW : 0; + else + pending |= did_throw ? CSTP_THROW : 0; + pending |= did_emsg ? CSTP_ERROR : 0; + pending |= got_int ? CSTP_INTERRUPT : 0; + cstack->cs_pending[cstack->cs_idx] = pending; + + /* It's mandatory that the current exception is stored in the + * cstack so that it can be rethrown at the ":endtry" or be + * discarded if the finally clause is left by a ":continue", + * ":break", ":return", ":finish", error, interrupt, or another + * exception. When emsg() is called for a missing ":endif" or + * a missing ":endwhile" detected here, the exception will be + * discarded. */ + if (did_throw && cstack->cs_exception[cstack->cs_idx] != + current_exception) + EMSG(_(e_internal)); + } + + /* + * Set cs_had_finally, so do_cmdline() will reset did_emsg, got_int, + * and did_throw and make the finally clause active. This will + * happen after emsg() has been called for a missing ":endif" or + * a missing ":endwhile" detected here, so that the following + * finally clause will be executed even then. + */ + cstack->cs_had_finally = TRUE; + } + } +} + +/* + * ":endtry" + */ + void +ex_endtry(eap) + exarg_T *eap; +{ + int idx; + int skip; + int rethrow = FALSE; + int pending = CSTP_NONE; + void *retvar = NULL; + struct condstack *cstack = eap->cstack; + + if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0) + eap->errmsg = (char_u *)N_("E602: :endtry without :try"); + else + { + /* + * Don't do something after an error, interrupt or throw in the try + * block, catch clause, or finally clause preceding this ":endtry" or + * when an error or interrupt occurred after a ":continue", ":break", + * ":return", or ":finish" in a try block or catch clause preceding this + * ":endtry" or when the try block never got active (because of an + * inactive surrounding conditional or after an error or interrupt or + * throw) or when there is a surrounding conditional and it has been + * made inactive by a ":continue", ":break", ":return", or ":finish" in + * the finally clause. The latter case need not be tested since then + * anything pending has already been discarded. */ + skip = did_emsg || got_int || did_throw || + !(cstack->cs_flags[cstack->cs_idx] & CSF_TRUE); + + if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY)) + { + /* Find the matching ":try" and report what's missing. */ + if (cstack->cs_flags[cstack->cs_idx] & CSF_WHILE) + eap->errmsg = e_endwhile; + else + eap->errmsg = e_endif; + idx = cstack->cs_idx; + do + --idx; + while (idx > 0 && !(cstack->cs_flags[idx] & CSF_TRY)); + rewind_conditionals(cstack, idx, CSF_WHILE, &cstack->cs_whilelevel); + skip = TRUE; + + /* + * If an exception is being thrown, discard it to prevent it from + * being rethrown at the end of this function. It would be + * discarded by the error message, anyway. Resets did_throw. + * This does not affect the script termination due to the error + * since "trylevel" is decremented after emsg() has been called. + */ + if (did_throw) + discard_current_exception(); + } + else + { + idx = cstack->cs_idx; + + /* + * If we stopped with the exception currently being thrown at this + * try conditional since we didn't know that it doesn't have + * a finally clause, we need to rethrow it after closing the try + * conditional. + */ + if (did_throw && (cstack->cs_flags[idx] & CSF_TRUE) + && !(cstack->cs_flags[idx] & CSF_FINALLY)) + rethrow = TRUE; + } + + /* If there was no finally clause, show the user when debugging or + * a breakpoint was encountered that the end of the try conditional has + * been reached: display the debug prompt (if not already done). Do + * this on normal control flow or when an exception was thrown, but not + * on an interrupt or error not converted to an exception or when + * a ":break", ":continue", ":return", or ":finish" is pending. These + * actions are carried out immediately. + */ + if ((rethrow || (!skip + && !(cstack->cs_flags[idx] & CSF_FINALLY) + && !cstack->cs_pending[idx])) + && dbg_check_skipped(eap)) + { + /* Handle a ">quit" debug command as if an interrupt had occurred + * before the ":endtry". That is, throw an interrupt exception and + * set "skip" and "rethrow". */ + if (got_int) + { + skip = TRUE; + (void)do_intthrow(cstack); + /* The do_intthrow() call may have reset did_throw or + * cstack->cs_pending[idx].*/ + rethrow = FALSE; + if (did_throw && !(cstack->cs_flags[idx] & CSF_FINALLY)) + rethrow = TRUE; + } + } + + /* + * If a ":return" is pending, we need to resume it after closing the + * try conditional; remember the return value. If there was a finally + * clause making an exception pending, we need to rethrow it. Make it + * the exception currently being thrown. + */ + if (!skip) + { + pending = cstack->cs_pending[idx]; + cstack->cs_pending[idx] = CSTP_NONE; + if (pending == CSTP_RETURN) + retvar = cstack->cs_retvar[idx]; + else if (pending & CSTP_THROW) + current_exception = cstack->cs_exception[idx]; + } + + /* + * Discard anything pending on an error, interrupt, or throw in the + * finally clause. If there was no ":finally", discard a pending + * ":continue", ":break", ":return", or ":finish" if an error or + * interrupt occurred afterwards, but before the ":endtry" was reached. + * If an exception was caught by the last of the catch clauses and there + * was no finally clause, finish the exception now. This happens also + * after errors except when this ":endtry" is not within a ":try". + * Restore "emsg_silent" if it has been reset by this try conditional. + */ + cleanup_conditionals(cstack, CSF_TRY | CSF_SILENT, TRUE); + + --cstack->cs_idx; + --cstack->cs_trylevel; + + if (!skip) + { + report_resume_pending(pending, + (pending == CSTP_RETURN) ? retvar : + (pending & CSTP_THROW) ? (void *)current_exception : NULL); + switch (pending) + { + case CSTP_NONE: + break; + + /* Reactivate a pending ":continue", ":break", ":return", + * ":finish" from the try block or a catch clause of this try + * conditional. This is skipped, if there was an error in an + * (unskipped) conditional command or an interrupt afterwards + * or if the finally clause is present and executed a new error, + * interrupt, throw, ":continue", ":break", ":return", or + * ":finish". */ + case CSTP_CONTINUE: + ex_continue(eap); + break; + case CSTP_BREAK: + ex_break(eap); + break; + case CSTP_RETURN: + do_return(eap, FALSE, FALSE, retvar); + break; + case CSTP_FINISH: + do_finish(eap, FALSE); + break; + + /* When the finally clause was entered due to an error, + * interrupt or throw (as opposed to a ":continue", ":break", + * ":return", or ":finish"), restore the pending values of + * did_emsg, got_int, and did_throw. This is skipped, if there + * was a new error, interrupt, throw, ":continue", ":break", + * ":return", or ":finish". in the finally clause. */ + default: + if (pending & CSTP_ERROR) + did_emsg = TRUE; + if (pending & CSTP_INTERRUPT) + got_int = TRUE; + if (pending & CSTP_THROW) + rethrow = TRUE; + break; + } + } + + if (rethrow) + /* Rethrow the current exception (within this cstack). */ + do_throw(cstack); + } +} + +/* + * Make conditionals inactive and discard what's pending in finally clauses + * until the conditional type searched for or a try conditional not in its + * finally clause is reached. If this is in an active catch clause, finish the + * caught exception. Return the cstack index where the search stopped. Values + * used for "searched_cond" are CSF_WHILE or CSF_TRY or 0, the latter meaning + * the innermost try conditional not in its finally clause. "inclusive" tells + * whether the conditional searched for should be made inactive itself (a try + * conditional not in its finally claused possibly find before is always made + * inactive). If "inclusive" is TRUE and "searched_cond" is CSF_TRY|CSF_SILENT, + * the saved former value of "emsg_silent", if reset when the try conditional + * finally reached was entered, is restored (unsed by ex_endtry()). This is + * normally done only when such a try conditional is left. + */ + int +cleanup_conditionals(cstack, searched_cond, inclusive) + struct condstack *cstack; + int searched_cond; + int inclusive; +{ + int idx; + int stop = FALSE; + + for (idx = cstack->cs_idx; idx >= 0; --idx) + { + if (cstack->cs_flags[idx] & CSF_TRY) + { + /* + * Discard anything pending in a finally clause and continue the + * search. There may also be a pending ":continue", ":break", + * ":return", or ":finish" before the finally clause. We must not + * discard it, unless an error or interrupt occurred afterwards. + */ + if (did_emsg || got_int || + (cstack->cs_flags[idx] & CSF_FINALLY)) + { + switch (cstack->cs_pending[idx]) + { + case CSTP_NONE: + break; + + case CSTP_CONTINUE: + case CSTP_BREAK: + case CSTP_FINISH: + report_discard_pending(cstack->cs_pending[idx], NULL); + cstack->cs_pending[idx] = CSTP_NONE; + break; + + case CSTP_RETURN: + report_discard_pending(CSTP_RETURN, + cstack->cs_retvar[idx]); + discard_pending_return(cstack->cs_retvar[idx]); + cstack->cs_pending[idx] = CSTP_NONE; + break; + + default: + if (cstack->cs_flags[idx] & CSF_FINALLY) + { + if (cstack->cs_pending[idx] & CSTP_THROW) + { + /* Cancel the pending exception. This is in the + * finally clause, so that the stack of the + * caught exceptions is not involved. */ + discard_exception((except_T *) + cstack->cs_exception[idx], + FALSE); + } + else + report_discard_pending(cstack->cs_pending[idx], + NULL); + cstack->cs_pending[idx] = CSTP_NONE; + } + break; + } + } + + /* + * Stop at a try conditional not in its finally clause. If this try + * conditional is in an active catch clause, finish the caught + * exception. + */ + if (!(cstack->cs_flags[idx] & CSF_FINALLY)) + { + if ((cstack->cs_flags[idx] & CSF_ACTIVE) + && (cstack->cs_flags[idx] & CSF_CAUGHT)) + finish_exception((except_T *)cstack->cs_exception[idx]); + /* Stop at this try conditional - except the try block never + * got active (because of an inactive surrounding conditional + * or when the ":try" appeared after an error or interrupt or + * throw). */ + if (cstack->cs_flags[idx] & CSF_TRUE) + { + if (searched_cond == 0 && !inclusive) + break; + stop = TRUE; + } + } + } + + /* Stop on the searched conditional type (even when the surrounding + * conditional is not active or something has been made pending). + * If "inclusive" is TRUE and "searched_cond" is CSF_TRY|CSF_SILENT, + * check first whether "emsg_silent" needs to be restored. */ + if (cstack->cs_flags[idx] & searched_cond) + { + if (!inclusive) + break; + stop = TRUE; + } + cstack->cs_flags[idx] &= ~CSF_ACTIVE; + if (stop && searched_cond != (CSF_TRY | CSF_SILENT)) + break; + + /* + * When leaving a try conditinal that reset "emsg_silent" on its entry + * after saving the original value, restore that value here and free the + * memory used to store it. + */ + if ((cstack->cs_flags[idx] & CSF_TRY) + && (cstack->cs_flags[idx] & CSF_SILENT)) + { + eslist_T *elem; + + elem = cstack->cs_emsg_silent_list; + cstack->cs_emsg_silent_list = elem->next; + emsg_silent = elem->saved_emsg_silent; + vim_free(elem); + cstack->cs_flags[idx] &= ~CSF_SILENT; + } + if (stop) + break; + } + return idx; +} + +/* + * Rewind conditionals until index "idx" is reached. "cond_type" and + * "cond_level" specify a conditional type and the address of a level variable + * which is to be decremented with each skipped conditional of the specified + * type. + */ + static void +rewind_conditionals(cstack, idx, cond_type, cond_level) + struct condstack *cstack; + int idx; + int cond_type; + int *cond_level; +{ + while (cstack->cs_idx > idx) + { + if (cstack->cs_flags[cstack->cs_idx] & cond_type) + --*cond_level; + --cstack->cs_idx; + } +} + +/* + * ":endfunction" when not after a ":function" + */ +/*ARGSUSED*/ + void +ex_endfunction(eap) + exarg_T *eap; +{ + EMSG(_("E193: :endfunction not inside a function")); +} + +/* + * Return TRUE if the string "p" looks like a ":while" command. + */ + int +has_while_cmd(p) + char_u *p; +{ + p = skipwhite(p); + while (*p == ':') + p = skipwhite(p + 1); + if (p[0] == 'w' && p[1] == 'h') + return TRUE; + return FALSE; +} + +#endif /* FEAT_EVAL */ |