43982ed49
Denys Vlasenko
2026-01-24
Subject
httpd: code shrink via "split-globals" trick
Binary
No binary (build failed)
Architecture & Compiler Flags
gcc -Wp,-MD,applets/.usage.d -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -Iinclude -Iinclude -o applets/usage applets/usage.c
Build Log
(log yok)
Commit Diff GitHub →
include/libbb.h+15 -0
| @@ -457,6 +457,11 @@ void *xmmap_anon(size_t size) FAST_FUNC; | |
| //sparc64,alpha,openrisc: fixed 8k pages | |
| #endif | |
| + | #if defined(__x86_64__) || defined(i386) |
| + | /* 0x7f would be better, but it causes alignment problems */ |
| + | # define ARCH_GLOBAL_PTR_OFF 0x80 |
| + | #endif |
| + | |
| #if defined BB_ARCH_FIXED_PAGESIZE | |
| # define IF_VARIABLE_ARCH_PAGESIZE(...) /*nothing*/ | |
| # define bb_getpagesize() BB_ARCH_FIXED_PAGESIZE | |
| @@ -2423,6 +2428,16 @@ void XZALLOC_CONST_PTR(const void *pptr, size_t size) FAST_FUNC; | |
| } \ | |
| } while (0) | |
| + | #if defined(ARCH_GLOBAL_PTR_OFF) |
| + | # define SET_OFFSET_PTR_TO_GLOBALS(x) \ |
| + | ASSIGN_CONST_PTR(&ptr_to_globals, (char*)(x) + ARCH_GLOBAL_PTR_OFF) |
| + | # define OFFSET_PTR_TO_GLOBALS \ |
| + | ((struct globals*)((char*)ptr_to_globals - ARCH_GLOBAL_PTR_OFF)) |
| + | #else |
| + | # define SET_OFFSET_PTR_TO_GLOBALS(x) SET_PTR_TO_GLOBALS(x) |
| + | # define OFFSET_PTR_TO_GLOBALS ptr_to_globals |
| + | #endif |
| + | |
| /* You can change LIBBB_DEFAULT_LOGIN_SHELL, but don't use it, | |
| * use bb_default_login_shell and following defines. | |
networking/httpd.c+3 -3
| @@ -484,7 +484,6 @@ static const struct { | |
| }; | |
| struct globals { | |
| - | int verbose; /* must be int (used by getopt32) */ |
| smallint flg_deny_all; | |
| #if ENABLE_FEATURE_HTTPD_GZIP | |
| /* client can handle gzip / we are going to send gzip */ | |
| @@ -494,6 +493,7 @@ struct globals { | |
| #if ENABLE_FEATURE_HTTPD_CGI | |
| smallint cgi_output; | |
| #endif | |
| + | int verbose; /* must be int (used by getopt32) */ |
| time_t last_mod; | |
| #if ENABLE_FEATURE_HTTPD_ETAG | |
| char *if_none_match; | |
| @@ -555,7 +555,7 @@ struct globals { | |
| #endif | |
| char iobuf[IOBUF_SIZE] ALIGN8; | |
| }; | |
| - | #define G (*ptr_to_globals) |
| + | #define G (*OFFSET_PTR_TO_GLOBALS) |
| #define verbose (G.verbose ) | |
| #define flg_deny_all (G.flg_deny_all ) | |
| #if ENABLE_FEATURE_HTTPD_GZIP | |
| @@ -598,7 +598,7 @@ enum { | |
| #define iobuf (G.iobuf ) | |
| #define INIT_G() do { \ | |
| setup_common_bufsiz(); \ | |
| - | SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| + | SET_OFFSET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \ | |
| IF_FEATURE_HTTPD_RANGES(range_start = -1;) \ | |
| bind_addr_or_port = STR(CONFIG_FEATURE_HTTPD_PORT_DEFAULT); \ | |