From: Paul Eggert Date: Fri, 27 Aug 2021 06:45:39 +0000 (-0700) Subject: regex: revert much of previous change X-Git-Tag: v1.0~2642 X-Git-Url: https://gitweb.git.savannah.gnu.org/gitweb/?a=commitdiff_plain;h=fecb49221e5efc3304600a26479aecc9bbc22b3c;p=gnulib.git regex: revert much of previous change Use a more-conservative change that syncs closer with glibc, and then merely marks regexec and __compat_regexec. --- diff --git a/ChangeLog b/ChangeLog index 80c2b83846..902c5262cf 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,17 +1,18 @@ 2021-08-26 Paul Eggert - regex: use C99-style array arg syntax + regex: use __attr_access and C99-style array arg This should help with some static checking. Derived from a suggestion by Martin Sebor in: https://sourceware.org/pipermail/libc-alpha/2021-August/130336.html - * lib/cdefs.h (__ARG_NELTS): New macro. * lib/regex.c: Ignore -Wvla for the whole file. - * lib/regex.h (_ARG_NELTS_): New macro. + * lib/regex.h (_REGEX_NELTS, _Attr_access_): New macros. Ignore -Wvla when declaring regexec. - * lib/regexec.c (regexec, __compat_regexec, re_copy_regs) - (re_search_internal, proceed_next_node, push_fail_stack) - (pop_fail_stack, set_regs, update_regs): - Use __ARG_NELTS for each array parameter whose size is another arg. + (re_compile_pattern, re_search, re_search2, re_match, re_match_2) + (regerror): Mark with _Attr_access_, as glibc does. + * lib/regex.h (regexec): + * lib/regexec.c (regexec, __compat_regexec): + Use _REGEX_NELTS for each array parameter whose size is another arg + but with an access pattern that cannot be captured with __attr_access. 2021-08-25 Bruno Haible diff --git a/lib/cdefs.h b/lib/cdefs.h index 13c5542bfd..4dac9d264d 100644 --- a/lib/cdefs.h +++ b/lib/cdefs.h @@ -634,13 +634,4 @@ _Static_assert (0, "IEEE 128-bits long double requires redirection on this platf # define __attribute_returns_twice__ /* Ignore. */ #endif -/* Specify the number of elements of a function's array parameter, - as in 'int f (int n, int a[__ARG_NELTS (n)]);'. */ -#if (defined __STDC_VERSION__ && 199901L <= __STDC_VERSION__ \ - && !defined __STDC_NO_VLA__) -# define __ARG_NELTS(n) n -#else -# define __ARG_NELTS(n) -#endif - #endif /* sys/cdefs.h */ diff --git a/lib/regex.h b/lib/regex.h index 118f9b4beb..adb69768ee 100644 --- a/lib/regex.h +++ b/lib/regex.h @@ -522,14 +522,12 @@ typedef struct /* Declarations for routines. */ -#ifndef _ARG_NELTS_ -# ifdef __ARG_NELTS -# define _ARG_NELTS_(arg) __ARG_NELTS (arg) -# elif (defined __STDC_VERSION__ && 199901L <= __STDC_VERSION__ \ +#ifndef _REGEX_NELTS +# if (defined __STDC_VERSION__ && 199901L <= __STDC_VERSION__ \ && !defined __STDC_NO_VLA__) -# define _ARG_NELTS_(n) n +# define _REGEX_NELTS(n) n # else -# define _ARG_NELTS_(n) +# define _REGEX_NELTS(n) # endif #endif @@ -680,7 +678,8 @@ extern int regcomp (regex_t *_Restrict_ __preg, extern int regexec (const regex_t *_Restrict_ __preg, const char *_Restrict_ __String, size_t __nmatch, - regmatch_t __pmatch[_Restrict_arr_ _ARG_NELTS_ (__nmatch)], + regmatch_t __pmatch[_Restrict_arr_ + _REGEX_NELTS (__nmatch)], int __eflags); extern size_t regerror (int __errcode, const regex_t *_Restrict_ __preg, diff --git a/lib/regexec.c b/lib/regexec.c index da1fb7fafa..83e9aaf8ca 100644 --- a/lib/regexec.c +++ b/lib/regexec.c @@ -31,11 +31,11 @@ static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop, static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts, re_dfastate_t **limited_sts, Idx last_node, Idx last_str_idx); -static reg_errcode_t -re_search_internal (const regex_t *preg, const char *string, Idx length, - Idx start, Idx last_start, Idx stop, size_t nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], - int eflags); +static reg_errcode_t re_search_internal (const regex_t *preg, + const char *string, Idx length, + Idx start, Idx last_start, Idx stop, + size_t nmatch, regmatch_t pmatch[], + int eflags); static regoff_t re_search_2_stub (struct re_pattern_buffer *bufp, const char *string1, Idx length1, const char *string2, Idx length2, @@ -47,29 +47,23 @@ static regoff_t re_search_stub (struct re_pattern_buffer *bufp, regoff_t range, Idx stop, struct re_registers *regs, bool ret_len); -static unsigned re_copy_regs (struct re_registers *regs, Idx nregs, - regmatch_t pmatch[__ARG_NELTS (static nregs)], - int regs_allocated); +static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, + Idx nregs, int regs_allocated); static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx); static Idx check_matching (re_match_context_t *mctx, bool fl_longest_match, Idx *p_match_first); static Idx check_halt_state_context (const re_match_context_t *mctx, const re_dfastate_t *state, Idx idx); -static void -update_regs (const re_dfa_t *dfa, Idx nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], - regmatch_t prev_idx_match[__ARG_NELTS (static nmatch)], - Idx cur_node, Idx cur_idx); -static reg_errcode_t -push_fail_stack (struct re_fail_stack_t *fs, - Idx str_idx, Idx dest_node, Idx nregs, - regmatch_t regs[__ARG_NELTS (static nregs)], - regmatch_t prevregs[__ARG_NELTS (static nregs)], - re_node_set *eps_via_nodes); +static void update_regs (const re_dfa_t *dfa, regmatch_t *pmatch, + regmatch_t *prev_idx_match, Idx cur_node, + Idx cur_idx, Idx nmatch); +static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs, + Idx str_idx, Idx dest_node, Idx nregs, + regmatch_t *regs, regmatch_t *prevregs, + re_node_set *eps_via_nodes); static reg_errcode_t set_regs (const regex_t *preg, const re_match_context_t *mctx, - size_t nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], + size_t nmatch, regmatch_t *pmatch, bool fl_backtrack); static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs); @@ -197,7 +191,7 @@ static reg_errcode_t extend_buffers (re_match_context_t *mctx, int min_len); int regexec (const regex_t *__restrict preg, const char *__restrict string, - size_t nmatch, regmatch_t pmatch[__ARG_NELTS (nmatch)], int eflags) + size_t nmatch, regmatch_t pmatch[_REGEX_NELTS (nmatch)], int eflags) { reg_errcode_t err; Idx start, length; @@ -218,8 +212,12 @@ regexec (const regex_t *__restrict preg, const char *__restrict string, } lock_lock (dfa->lock); - err = re_search_internal (preg, string, length, start, length, - length, preg->no_sub ? 0 : nmatch, pmatch, eflags); + if (preg->no_sub) + err = re_search_internal (preg, string, length, start, length, + length, 0, NULL, eflags); + else + err = re_search_internal (preg, string, length, start, length, + length, nmatch, pmatch, eflags); lock_unlock (dfa->lock); return err != REG_NOERROR; } @@ -237,7 +235,7 @@ int attribute_compat_text_section __compat_regexec (const regex_t *__restrict preg, const char *__restrict string, size_t nmatch, - regmatch_t pmatch[__ARG_NELTS (nmatch)], int eflags) + regmatch_t pmatch[_REGEX_NELTS (nmatch)], int eflags) { return regexec (preg, string, nmatch, pmatch, eflags & (REG_NOTBOL | REG_NOTEOL)); @@ -436,7 +434,7 @@ re_search_stub (struct re_pattern_buffer *bufp, const char *string, Idx length, else if (regs != NULL) { /* If caller wants register contents data back, copy them. */ - bufp->regs_allocated = re_copy_regs (regs, nregs, pmatch, + bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs, bufp->regs_allocated); if (__glibc_unlikely (bufp->regs_allocated == REGS_UNALLOCATED)) rval = -2; @@ -459,8 +457,7 @@ re_search_stub (struct re_pattern_buffer *bufp, const char *string, Idx length, } static unsigned -re_copy_regs (struct re_registers *regs, Idx nregs, - regmatch_t pmatch[__ARG_NELTS (static nregs)], +re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, Idx nregs, int regs_allocated) { int rval = REGS_REALLOCATE; @@ -588,8 +585,7 @@ static reg_errcode_t __attribute_warn_unused_result__ re_search_internal (const regex_t *preg, const char *string, Idx length, Idx start, Idx last_start, Idx stop, size_t nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], - int eflags) + regmatch_t pmatch[], int eflags) { reg_errcode_t err; const re_dfa_t *dfa = preg->buffer; @@ -1214,9 +1210,8 @@ check_halt_state_context (const re_match_context_t *mctx, return -1 on match failure, -2 on error. */ static Idx -proceed_next_node (const re_match_context_t *mctx, Idx nregs, - regmatch_t regs[__ARG_NELTS (static nregs)], - regmatch_t prevregs[__ARG_NELTS (static nregs)], +proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs, + regmatch_t *prevregs, Idx *pidx, Idx node, re_node_set *eps_via_nodes, struct re_fail_stack_t *fs) { @@ -1326,9 +1321,7 @@ proceed_next_node (const re_match_context_t *mctx, Idx nregs, static reg_errcode_t __attribute_warn_unused_result__ push_fail_stack (struct re_fail_stack_t *fs, Idx str_idx, Idx dest_node, - Idx nregs, - regmatch_t regs[__ARG_NELTS (static nregs)], - regmatch_t prevregs[__ARG_NELTS (static nregs)], + Idx nregs, regmatch_t *regs, regmatch_t *prevregs, re_node_set *eps_via_nodes) { reg_errcode_t err; @@ -1356,8 +1349,7 @@ push_fail_stack (struct re_fail_stack_t *fs, Idx str_idx, Idx dest_node, static Idx pop_fail_stack (struct re_fail_stack_t *fs, Idx *pidx, Idx nregs, - regmatch_t regs[__ARG_NELTS (static nregs)], - regmatch_t prevregs[__ARG_NELTS (static nregs)], + regmatch_t *regs, regmatch_t *prevregs, re_node_set *eps_via_nodes) { if (fs == NULL || fs->num == 0) @@ -1387,7 +1379,7 @@ pop_fail_stack (struct re_fail_stack_t *fs, Idx *pidx, Idx nregs, static reg_errcode_t __attribute_warn_unused_result__ set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], bool fl_backtrack) + regmatch_t *pmatch, bool fl_backtrack) { const re_dfa_t *dfa = preg->buffer; Idx idx, cur_node; @@ -1423,7 +1415,7 @@ set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch, for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;) { - update_regs (dfa, nmatch, pmatch, prev_idx_match, cur_node, idx); + update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch); if ((idx == pmatch[0].rm_eo && cur_node == mctx->last_node) || (fs && re_node_set_contains (&eps_via_nodes, cur_node))) @@ -1495,10 +1487,8 @@ free_fail_stack_return (struct re_fail_stack_t *fs) } static void -update_regs (const re_dfa_t *dfa, Idx nmatch, - regmatch_t pmatch[__ARG_NELTS (static nmatch)], - regmatch_t prev_idx_match[__ARG_NELTS (static nmatch)], - Idx cur_node, Idx cur_idx) +update_regs (const re_dfa_t *dfa, regmatch_t *pmatch, + regmatch_t *prev_idx_match, Idx cur_node, Idx cur_idx, Idx nmatch) { int type = dfa->nodes[cur_node].type; if (type == OP_OPEN_SUBEXP)