git/grep.h
Ævar Arnfjörð Bjarmason cbe81e653f grep/pcre2: move back to thread-only PCREv2 structures
Change the setup of the "pcre2_general_context" to happen per-thread
in compile_pcre2_pattern() instead of in grep_init().

This change brings it in line with how the rest of the pcre2_* members
in the grep_pat structure are set up.

As noted in the preceding commit the approach 513f2b0bbd (grep: make
PCRE2 aware of custom allocator, 2019-10-16) took to allocate the
pcre2_general_context seems to have been initially based on a
misunderstanding of how PCREv2 memory allocation works.

The approach of creating a global context in grep_init() is just added
complexity for almost zero gain. On my system it's 24 bytes saved
per-thread. For comparison PCREv2 will then go on to allocate at least
a kilobyte for its own thread-local state.

As noted in 6d423dd542 (grep: don't redundantly compile throwaway
patterns under threading, 2017-05-25) the grep code is intentionally
not trying to micro-optimize allocations by e.g. sharing some PCREv2
structures globally, while making others thread-local.

So let's remove this special case and make all of them thread-local
again for simplicity. With this change we could move the
pcre2_{malloc,free} functions around to live closer to their current
use. I'm not doing that here to keep this change small, that cleanup
will be done in a follow-up commit.

See also the discussion in 94da9193a6 (grep: add support for PCRE v2,
2017-06-01) about thread safety, and Johannes's comments[1] to the
effect that we should be doing what this patch is doing.

1. https://lore.kernel.org/git/nycvar.QRO.7.76.6.1908052120302.46@tvgsbejvaqbjf.bet/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-17 16:32:19 -08:00

219 lines
5 KiB
C

#ifndef GREP_H
#define GREP_H
#include "color.h"
#ifdef USE_LIBPCRE2
#define PCRE2_CODE_UNIT_WIDTH 8
#include <pcre2.h>
#if (PCRE2_MAJOR >= 10 && PCRE2_MINOR >= 36) || PCRE2_MAJOR >= 11
#define GIT_PCRE2_VERSION_10_36_OR_HIGHER
#endif
#if (PCRE2_MAJOR >= 10 && PCRE2_MINOR >= 34) || PCRE2_MAJOR >= 11
#define GIT_PCRE2_VERSION_10_34_OR_HIGHER
#endif
#else
typedef int pcre2_code;
typedef int pcre2_match_data;
typedef int pcre2_compile_context;
typedef int pcre2_general_context;
#endif
#ifndef PCRE2_MATCH_INVALID_UTF
/* PCRE2_MATCH_* dummy also with !USE_LIBPCRE2, for test-pcre2-config.c */
#define PCRE2_MATCH_INVALID_UTF 0
#endif
#include "thread-utils.h"
#include "userdiff.h"
struct repository;
enum grep_pat_token {
GREP_PATTERN,
GREP_PATTERN_HEAD,
GREP_PATTERN_BODY,
GREP_AND,
GREP_OPEN_PAREN,
GREP_CLOSE_PAREN,
GREP_NOT,
GREP_OR
};
enum grep_context {
GREP_CONTEXT_HEAD,
GREP_CONTEXT_BODY
};
enum grep_header_field {
GREP_HEADER_FIELD_MIN = 0,
GREP_HEADER_AUTHOR = GREP_HEADER_FIELD_MIN,
GREP_HEADER_COMMITTER,
GREP_HEADER_REFLOG,
/* Must be at the end of the enum */
GREP_HEADER_FIELD_MAX
};
enum grep_color {
GREP_COLOR_CONTEXT,
GREP_COLOR_FILENAME,
GREP_COLOR_FUNCTION,
GREP_COLOR_LINENO,
GREP_COLOR_COLUMNNO,
GREP_COLOR_MATCH_CONTEXT,
GREP_COLOR_MATCH_SELECTED,
GREP_COLOR_SELECTED,
GREP_COLOR_SEP,
NR_GREP_COLORS
};
struct grep_pat {
struct grep_pat *next;
const char *origin;
int no;
enum grep_pat_token token;
char *pattern;
size_t patternlen;
enum grep_header_field field;
regex_t regexp;
pcre2_code *pcre2_pattern;
pcre2_match_data *pcre2_match_data;
pcre2_compile_context *pcre2_compile_context;
pcre2_general_context *pcre2_general_context;
const uint8_t *pcre2_tables;
uint32_t pcre2_jit_on;
unsigned fixed:1;
unsigned is_fixed:1;
unsigned ignore_case:1;
unsigned word_regexp:1;
};
enum grep_expr_node {
GREP_NODE_ATOM,
GREP_NODE_NOT,
GREP_NODE_AND,
GREP_NODE_TRUE,
GREP_NODE_OR
};
enum grep_pattern_type {
GREP_PATTERN_TYPE_UNSPECIFIED = 0,
GREP_PATTERN_TYPE_BRE,
GREP_PATTERN_TYPE_ERE,
GREP_PATTERN_TYPE_FIXED,
GREP_PATTERN_TYPE_PCRE
};
struct grep_expr {
enum grep_expr_node node;
unsigned hit;
union {
struct grep_pat *atom;
struct grep_expr *unary;
struct {
struct grep_expr *left;
struct grep_expr *right;
} binary;
} u;
};
struct grep_opt {
struct grep_pat *pattern_list;
struct grep_pat **pattern_tail;
struct grep_pat *header_list;
struct grep_pat **header_tail;
struct grep_expr *pattern_expression;
struct repository *repo;
const char *prefix;
int prefix_length;
regex_t regexp;
int linenum;
int columnnum;
int invert;
int ignore_case;
int status_only;
int name_only;
int unmatch_name_only;
int count;
int word_regexp;
int fixed;
int all_match;
#define GREP_BINARY_DEFAULT 0
#define GREP_BINARY_NOMATCH 1
#define GREP_BINARY_TEXT 2
int binary;
int allow_textconv;
int extended;
int use_reflog_filter;
int pcre2;
int relative;
int pathname;
int null_following_name;
int only_matching;
int color;
int max_depth;
int funcname;
int funcbody;
int extended_regexp_option;
int pattern_type_option;
int ignore_locale;
char colors[NR_GREP_COLORS][COLOR_MAXLEN];
unsigned pre_context;
unsigned post_context;
unsigned last_shown;
int show_hunk_mark;
int file_break;
int heading;
void *priv;
void (*output)(struct grep_opt *opt, const void *data, size_t size);
void *output_priv;
};
int grep_config(const char *var, const char *value, void *);
void grep_init(struct grep_opt *, struct repository *repo, const char *prefix);
void grep_commit_pattern_type(enum grep_pattern_type, struct grep_opt *opt);
void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, const char *origin, int no, enum grep_pat_token t);
void append_grep_pattern(struct grep_opt *opt, const char *pat, const char *origin, int no, enum grep_pat_token t);
void append_header_grep_pattern(struct grep_opt *, enum grep_header_field, const char *);
void compile_grep_patterns(struct grep_opt *opt);
void free_grep_patterns(struct grep_opt *opt);
int grep_buffer(struct grep_opt *opt, char *buf, unsigned long size);
struct grep_source {
char *name;
enum grep_source_type {
GREP_SOURCE_OID,
GREP_SOURCE_FILE,
GREP_SOURCE_BUF,
} type;
void *identifier;
char *buf;
unsigned long size;
char *path; /* for attribute lookups */
struct userdiff_driver *driver;
};
void grep_source_init(struct grep_source *gs, enum grep_source_type type,
const char *name, const char *path,
const void *identifier);
void grep_source_clear_data(struct grep_source *gs);
void grep_source_clear(struct grep_source *gs);
void grep_source_load_driver(struct grep_source *gs,
struct index_state *istate);
int grep_source(struct grep_opt *opt, struct grep_source *gs);
struct grep_opt *grep_opt_dup(const struct grep_opt *opt);
int grep_threads_ok(const struct grep_opt *opt);
/*
* Mutex used around access to the attributes machinery if
* opt->use_threads. Must be initialized/destroyed by callers!
*/
extern int grep_use_locks;
extern pthread_mutex_t grep_attr_mutex;
#endif