The silver search(ag)比ack-grep还快

今天用ag搜索android4.1的代码，发现总是被一个长得让崩溃的.json文件匹配(键入ag ::layout)搞得没法健康地查看ag.el的结果。

一看ag的代码才知道这长行打印压制还是个未完成功能

src/options.h:48:30:    int print_long_lines; /* TODO: support this in print.c */

好在作者的C代码简洁明了，使得我可以很快写出一个Patch，使用-M 参数来压制长行输出。patch邮件已经发送。我自己也backup一下：

diff --git a/src/options.c b/src/options.c
index b08903f..2f4b18e 100644
--- a/src/options.c
+++ b/src/options.c
@@ -77,6 +77,8 @@ Search options:\n\
-p --path-to-agignore STRING\n\
Use .agignore file at STRING\n\
--print-long-lines Print matches on very long lines (Default: >2k characters)\n\
+-M --max-printable-line-length NUM \n\
+ Skip print the matching lines that have a length bigger than NUM\n \
-Q --literal Don't parse PATTERN as a regular expression\n\
-s --case-sensitive Match case sensitively (Enabled by default)\n\
-S --smart-case Match case insensitively unless PATTERN contains\n\
@@ -115,6 +117,7 @@ void init_options() {
opts.color_path = ag_strdup(color_path);
opts.color_match = ag_strdup(color_match);
opts.color_line_number = ag_strdup(color_line_number);
+ opts.max_printable_line_length = DEFAULT_MAX_PRINTABLE_LINE_LENGTH;
}

void cleanup_options() {
@@ -221,6 +224,7 @@ void parse_options(int argc, char **argv, char **base_paths[], char **paths[]) {
{ "version", no_argument, &version, 1 },
{ "word-regexp", no_argument, NULL, 'w' },
{ "workers", required_argument, NULL, 0 },
+ { "max-printable-line-length", required_argument, NULL, 'M' },
{ NULL, 0, NULL, 0 }
};

@@ -253,7 +257,7 @@ void parse_options(int argc, char **argv, char **base_paths[], char **paths[]) {
opts.stdout_inode = statbuf.st_ino;
}

- while ((ch = getopt_long(argc, argv, "A:aB:C:DG:g:fhiLlm:np:QRrSsvVtuUwz", longopts, &opt_index)) != -1) {
+ while ((ch = getopt_long(argc, argv, "A:aB:C:DG:g:fhiLlm:M:np:QRrSsvVtuUwz", longopts, &opt_index)) != -1) {
switch (ch) {
case 'A':
opts.after = atoi(optarg);
@@ -305,6 +309,9 @@ void parse_options(int argc, char **argv, char **base_paths[], char **paths[]) {
case 'm':
opts.max_matches_per_file = atoi(optarg);
break;
+ case 'M':
+ opts.max_printable_line_length = atoi(optarg);
+ break;
case 'n':
opts.recurse_dirs = 0;
break;
diff --git a/src/options.h b/src/options.h
index 5049ab5..b4d2468 100644
--- a/src/options.h
+++ b/src/options.h
@@ -7,6 +7,7 @@
#include <pcre.h>

#define DEFAULT_CONTEXT_LEN 2
+#define DEFAULT_MAX_PRINTABLE_LINE_LENGTH 2000

enum case_behavior {
CASE_SENSITIVE,
@@ -45,6 +46,7 @@ typedef struct {
int print_heading;
int print_line_numbers;
int print_long_lines; /* TODO: support this in print.c */
+ int max_printable_line_length;
pcre *re;
pcre_extra *re_extra;
int recurse_dirs;
diff --git a/src/print.c b/src/print.c
index dc11594..4be9874 100644
--- a/src/print.c
+++ b/src/print.c
@@ -34,6 +34,15 @@ void print_binary_file_matches(const char* path) {
fprintf(out_fd, "Binary file %s matches.\n", path);
}

+static void check_printable(int len, int *printable) {
+ if (len > opts.max_printable_line_length) {
+ *printable = FALSE;
+ fprintf(out_fd, "+EVIL+MARK+VERY+LONG+LINES+HERE\n");
+ } else {
+ *printable = TRUE;
+ }
+}
+
void print_file_matches(const char* path, const char* buf, const int buf_len, const match matches[], const int matches_len) {
int line = 1;
char **context_prev_lines = NULL;
@@ -49,6 +58,7 @@ void print_file_matches(const char* path, const char* buf, const int buf_len, co
int i, j;
int in_a_match = FALSE;
int printing_a_match = FALSE;
+ int printable = TRUE;

if (opts.ackmate) {
sep = ':';
@@ -129,7 +139,8 @@ void print_file_matches(const char* path, const char* buf, const int buf_len, co
}
j = prev_line_offset;
/* print up to current char */
- for (; j <= i; j++) {
+ check_printable(i - prev_line_offset, &printable);
+ for (; j <= i && printable; j++) {
fputc(buf[j], out_fd);
}
} else {
@@ -141,7 +152,8 @@ void print_file_matches(const char* path, const char* buf, const int buf_len, co
if (printing_a_match && opts.color) {
fprintf(out_fd, "%s", opts.color_match);
}
- for (j = prev_line_offset; j <= i; j++) {
+ check_printable(i - prev_line_offset, &printable);
+ for (j = prev_line_offset; j <= i && printable; j++) {
if (j == matches[last_printed_match].end && last_printed_match < matches_len) {
if (opts.color) {
fprintf(out_fd, "%s", color_reset);