Commit 2a8b823e authored by Justin Erenkrantz's avatar Justin Erenkrantz
Browse files

This patch optimizes away some strlen and strcat calls in 

ap_directory_walk.  The strlen calls, in particular, had
ranked as a top bottleneck in the usr-space code in recent
performance profiling.

Submitted by:	Brian Pane <bpane@pacbell.net>
Reviewed by:	Justin Erenkrantz


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91746 13f79535-47bb-0310-9956-ffa450edef68
parent 2945a474

CHANGES

+3 −0
Original line number Diff line number Diff line 
Changes with Apache 2.0.28-dev



  *) Optimize usage of strlen and strcat in ap_directory_walk.

     [Brian Pane <bpane@pacbell.net>]



  *) Introduce an Apache mod_ssl initial configuration template 

     (ssl.conf, generated from ssl-std.conf).  [Ralf S. Engelschall]

server/request.c

+21 −9
Original line number Diff line number Diff line
@@ -545,6 +545,11 @@ AP_DECLARE(int) ap_directory_walk(request_rec *r) 
        char *buf;

        unsigned int seg, startseg;



        /* Invariant: from the first time filename_len is set until

         * it goes out of scope, filename_len==strlen(r->filename)

         */

        size_t filename_len;



        /*

         * We must play our own mimi-merge game here, for the few 

         * running dir_config values we care about within dir_walk.
@@ -569,10 +574,11 @@ AP_DECLARE(int) ap_directory_walk(request_rec *r) 
        rv = apr_filepath_root((const char **)&r->filename,

                               (const char **)&r->path_info,

                               APR_FILEPATH_TRUENAME, r->pool);

        filename_len = strlen(r->filename);

        /* Space for terminating null and an extra / is required. */

        buflen = strlen(r->filename) + strlen(r->path_info) + 2;

        buflen = filename_len + strlen(r->path_info) + 2;

        buf = apr_palloc(r->pool, buflen);

        strcpy (buf, r->filename);

        memcpy(buf, r->filename, filename_len + 1);

        r->filename = buf;

        r->finfo.valid = APR_FINFO_TYPE;

        r->finfo.filetype = APR_DIR; /* It's the root, of course it's a dir */
@@ -591,8 +597,9 @@ AP_DECLARE(int) ap_directory_walk(request_rec *r) 
        

            /* We have no trailing slash, but we sure would appreciate one...

             */

            if (sec_idx && r->filename[strlen(r->filename)-1] != '/') {

                strcat(r->filename, "/");

            if (sec_idx && r->filename[filename_len-1] != '/') {

                r->filename[filename_len++] = '/';

                r->filename[filename_len] = 0;

            }



            /* Begin *this* level by looking for matching <Directory> sections
@@ -761,7 +768,7 @@ minimerge2: 
            /* That temporary trailing slash was useful, now drop it.

             */

            if (seg > startseg) {

                r->filename[strlen(r->filename) - 1] = '\0';

                r->filename[--filename_len] = '\0';

            }



            /* Time for all good things to come to an end?
@@ -775,17 +782,21 @@ minimerge2: 
             * below as necessary...

             */

        

            seg_name = strchr(r->filename, '\0');

            seg_name = r->filename + filename_len;

            delim = strchr(r->path_info + (*r->path_info == '/' ? 1 : 0), '/');

            if (delim) {

                size_t path_info_len = delim - r->path_info;

                *delim = '\0';

                strcpy(seg_name, r->path_info);

                memcpy(seg_name, r->path_info, path_info_len + 1);

                filename_len += path_info_len;

                r->path_info = delim;

                *delim = '/';

            }

            else {

                strcpy(seg_name, r->path_info);

                r->path_info = strchr(r->path_info, '\0');

                size_t path_info_len = strlen(r->path_info);

                memcpy(seg_name, r->path_info, path_info_len + 1);

                filename_len += path_info_len;

                r->path_info += path_info_len;

            }

            if (*seg_name == '/') 

                ++seg_name;
@@ -850,6 +861,7 @@ minimerge2: 
                 * filename in tandem to properly correlate these.

                 */

                strcpy(seg_name, r->finfo.name);

                filename_len = strlen(r->filename);

            }



            if (r->finfo.filetype == APR_LNK) {