[libcamera-devel] libcamera: ipa_module: Use ElfW() macro for native word size

2801 diff mbox series

Access the ELF types corresponding to the native word size using the
ElfW() macro instead of template types. This is the standard method and
simplifies the code.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 src/libcamera/ipa_module.cpp | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

Hi Laurent,

On 06/02/2020 21:59, Laurent Pinchart wrote:
> Access the ELF types corresponding to the native word size using the
> ElfW() macro instead of template types. This is the standard method and
> simplifies the code.

Excellent, You beat me to it. I was going to look at this having
identified the ElfW macro from the other series.

Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  src/libcamera/ipa_module.cpp | 27 ++++++++++-----------------
>  1 file changed, 10 insertions(+), 17 deletions(-)
> 
> diff --git a/src/libcamera/ipa_module.cpp b/src/libcamera/ipa_module.cpp
> index 2c355ea8b5e5..de65525b8319 100644
> --- a/src/libcamera/ipa_module.cpp
> +++ b/src/libcamera/ipa_module.cpp
> @@ -13,6 +13,7 @@
>  #include <elf.h>
>  #include <errno.h>
>  #include <fcntl.h>
> +#include <link.h>
>  #include <string.h>
>  #include <sys/mman.h>
>  #include <sys/stat.h>
> @@ -94,25 +95,24 @@ int elfVerifyIdent(void *map, size_t soSize)
>   * \return zero or error code, address or nullptr, size of symbol or zero,
>   * respectively
>   */
> -template<class ElfHeader, class SecHeader, class SymHeader>
>  std::tuple<void *, size_t>
>  elfLoadSymbol(void *map, size_t soSize, const char *symbol)
>  {
> -	ElfHeader *eHdr = elfPointer<ElfHeader>(map, 0, soSize);
> +	ElfW(Ehdr) *eHdr = elfPointer<ElfW(Ehdr)>(map, 0, soSize);
>  	if (!eHdr)
>  		return std::make_tuple(nullptr, 0);
>  
>  	off_t offset = eHdr->e_shoff + eHdr->e_shentsize * eHdr->e_shstrndx;
> -	SecHeader *sHdr = elfPointer<SecHeader>(map, offset, soSize);
> +	ElfW(Shdr) *sHdr = elfPointer<ElfW(Shdr)>(map, offset, soSize);
>  	if (!sHdr)
>  		return std::make_tuple(nullptr, 0);
>  	off_t shnameoff = sHdr->sh_offset;
>  
>  	/* Locate .dynsym section header. */
> -	SecHeader *dynsym = nullptr;
> +	ElfW(Shdr) *dynsym = nullptr;
>  	for (unsigned int i = 0; i < eHdr->e_shnum; i++) {
>  		offset = eHdr->e_shoff + eHdr->e_shentsize * i;
> -		sHdr = elfPointer<SecHeader>(map, offset, soSize);
> +		sHdr = elfPointer<ElfW(Shdr)>(map, offset, soSize);
>  		if (!sHdr)
>  			return std::make_tuple(nullptr, 0);
>  
> @@ -133,17 +133,17 @@ elfLoadSymbol(void *map, size_t soSize, const char *symbol)
>  	}
>  
>  	offset = eHdr->e_shoff + eHdr->e_shentsize * dynsym->sh_link;
> -	sHdr = elfPointer<SecHeader>(map, offset, soSize);
> +	sHdr = elfPointer<ElfW(Shdr)>(map, offset, soSize);
>  	if (!sHdr)
>  		return std::make_tuple(nullptr, 0);
>  	off_t dynsym_nameoff = sHdr->sh_offset;
>  
>  	/* Locate symbol in the .dynsym section. */
> -	SymHeader *targetSymbol = nullptr;
> +	ElfW(Sym) *targetSymbol = nullptr;
>  	unsigned int dynsym_num = dynsym->sh_size / dynsym->sh_entsize;
>  	for (unsigned int i = 0; i < dynsym_num; i++) {
>  		offset = dynsym->sh_offset + dynsym->sh_entsize * i;
> -		SymHeader *sym = elfPointer<SymHeader>(map, offset, soSize);
> +		ElfW(Sym) *sym = elfPointer<ElfW(Sym)>(map, offset, soSize);
>  		if (!sym)
>  			return std::make_tuple(nullptr, 0);
>  
> @@ -169,7 +169,7 @@ elfLoadSymbol(void *map, size_t soSize, const char *symbol)
>  	if (targetSymbol->st_shndx >= eHdr->e_shnum)
>  		return std::make_tuple(nullptr, 0);
>  	offset = eHdr->e_shoff + targetSymbol->st_shndx * eHdr->e_shentsize;
> -	sHdr = elfPointer<SecHeader>(map, offset, soSize);
> +	sHdr = elfPointer<ElfW(Shdr)>(map, offset, soSize);
>  	if (!sHdr)
>  		return std::make_tuple(nullptr, 0);
>  	offset = sHdr->sh_offset + (targetSymbol->st_value - sHdr->sh_addr);
> @@ -310,14 +310,7 @@ int IPAModule::loadIPAModuleInfo()
>  	if (ret)
>  		goto unmap;
>  
> -	if (sizeof(unsigned long) == 4)
> -		std::tie(data, dataSize) =
> -			elfLoadSymbol<Elf32_Ehdr, Elf32_Shdr, Elf32_Sym>
> -				     (map, soSize, "ipaModuleInfo");
> -	else
> -		std::tie(data, dataSize) =
> -			elfLoadSymbol<Elf64_Ehdr, Elf64_Shdr, Elf64_Sym>
> -				     (map, soSize, "ipaModuleInfo");
> +	std::tie(data, dataSize) = elfLoadSymbol(map, soSize, "ipaModuleInfo");
>  
>  	if (data && dataSize == sizeof(info_))
>  		memcpy(&info_, data, dataSize);
>