libmicrohttpd

commit ef3bdbd92e107624899300351840bd8f787480c7
parent 49b0e0ce8f929b326b6e926e26dede64f29756d0
Author: Christian Grothoff <christian@grothoff.org>
Date:   Wed, 30 Jan 2013 12:26:27 +0000

Hello,

could be possible to change declarations for arrays of strings in the file reason_phrase.c?

Currently it is static const char * []. This places all strings into .rodata section and pointers to them into LMA of .text and also into .data in VMA.

E.g. for an ARM Cortex M3 (flash + SRAM) compiled with a arm-none-eabi-gcc
static const char *one_hundred[] = {
  "Continue",
  "Switching Protocols",
  "Processing"
};


Strings "Continue", "Switching Protocols", "Processing" are stored in flash. Also an array with pointers to strings is stored in flash. In addition, this array is copied into SRAM (+16 bytes). If you would change it to "static const char * const one_hundred[]" ... it would occupy only flash.

and
struct MHD_Reason_Block
{
......
  const char * const * data;
};

I agree, it is not relevant on a PC but on most microcontroller the SRAM is a limiting factor not the rom(flash).

Best
Martin Velek







Diffstat:
M
ChangeLog
 | 
4
++++
M
src/daemon/reason_phrase.c
 | 
12
++++++------

2 files changed, 10 insertions(+), 6 deletions(-)
diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Jan 30 13:09:30 CET 2013
+	Adding more 'const' to allow keeping of reason phrases in ROM.
+	(see mailinglist). -CG/MV
+
 Tue Jan 29 21:27:56 CET 2013
 	Make code work with PlibC 0.1.7 (which removed plibc_init_utf8).
 	Only relevant for W32. Fixes #2734. -CG
diff --git a/src/daemon/reason_phrase.c b/src/daemon/reason_phrase.c
@@ -33,13 +33,13 @@
 
 static const char *invalid_hundred[] = { NULL };
 
-static const char *one_hundred[] = {
+static const char *const one_hundred[] = {
   "Continue",
   "Switching Protocols",
   "Processing"
 };
 
-static const char *two_hundred[] = {
+static const char *const two_hundred[] = {
   "OK",
   "Created",
   "Accepted",
@@ -50,7 +50,7 @@ static const char *two_hundred[] = {
   "Multi Status"
 };
 
-static const char *three_hundred[] = {
+static const char *const three_hundred[] = {
   "Multiple Choices",
   "Moved Permanently",
   "Moved Temporarily",
@@ -61,7 +61,7 @@ static const char *three_hundred[] = {
   "Temporary Redirect"
 };
 
-static const char *four_hundred[] = {
+static const char *const four_hundred[] = {
   "Bad Request",
   "Unauthorized",
   "Payment Required",
@@ -116,7 +116,7 @@ static const char *four_hundred[] = {
   "Unavailable For Legal Reasons"
 };
 
-static const char *five_hundred[] = {
+static const char *const five_hundred[] = {
   "Internal Server Error",
   "Not Implemented",
   "Bad Gateway",
@@ -134,7 +134,7 @@ static const char *five_hundred[] = {
 struct MHD_Reason_Block
 {
   unsigned int max;
-  const char **data;
+  const char *const*data;
 };
 
 #define BLOCK(m) { (sizeof(m) / sizeof(char*)), m }