8:26 a.m.
On Friday 17 April 2015 15:15:26 Maros Zatko wrote:
On 04/17/2015 10:56 AM, Pino Toscano wrote:
> On Thursday 16 April 2015 16:51:48 Maros Zatko wrote:
>> ---
>> src/filearch.c | 18 +++++++++++++-----
>> 1 file changed, 13 insertions(+), 5 deletions(-)
>>
>> diff --git a/src/filearch.c b/src/filearch.c
>> index df65c98..5de2959 100644
>> --- a/src/filearch.c
>> +++ b/src/filearch.c
>> @@ -59,8 +59,9 @@ cleanup_magic_t_free (void *ptr)
>> # endif
>>
>> COMPILE_REGEXP (re_file_elf,
>> - "ELF.*(?:executable|shared object|relocatable),
(.+?),", 0)
>> -COMPILE_REGEXP (re_elf_ppc64, "64.*PowerPC", 0)
>> + "ELF.*(MSB|LSB).*(?:executable|shared object|relocatable),
(.+?),", 0)
>> +COMPILE_REGEXP (re_elf_ppc64, "MSB.*64.*PowerPC", 0)
>> +COMPILE_REGEXP (re_elf_ppc64le, "LSB.*64.*PowerPC", 0)
>>
>> /* Convert output from 'file' command on ELF files to the canonical
>> * architecture string. Caller must free the result.
>> @@ -87,6 +88,8 @@ canonical_elf_arch (guestfs_h *g, const char *elf_arch)
>> r = "ia64";
>> else if (match (g, elf_arch, re_elf_ppc64))
>> r = "ppc64";
>> + else if (match (g, elf_arch, re_elf_ppc64le))
>> + r = "ppc64le";
>> else if (strstr (elf_arch, "PowerPC"))
>> r = "ppc";
>> else if (strstr (elf_arch, "ARM aarch64"))
>> @@ -114,6 +117,7 @@ magic_for_file (guestfs_h *g, const char *filename, bool
*loading_ok,
>> {
>> int flags;
>> CLEANUP_MAGIC_T_FREE magic_t m = NULL;
>> + CLEANUP_FREE char *tmp = NULL;
>> const char *line;
>> char *elf_arch;
>>
>> @@ -145,7 +149,7 @@ magic_for_file (guestfs_h *g, const char *filename, bool
*loading_ok,
>> if (loading_ok)
>> *loading_ok = true;
>>
>> - elf_arch = match1 (g, line, re_file_elf);
>> + match2 (g, line, re_file_elf, &tmp, &elf_arch);
>> if (elf_arch == NULL) {
> Better switch the checking from elf_arch (which is not touched if
> match2 fails, so being an uninitialized pointer) to the return value
> of match2.
>
>> error (g, "no re_file_elf match in '%s'", line);
>> return NULL;
>> @@ -315,6 +319,8 @@ guestfs_impl_file_architecture (guestfs_h *g, const char
*path)
>> {
>> CLEANUP_FREE char *file = NULL;
>> CLEANUP_FREE char *elf_arch = NULL;
>> + CLEANUP_FREE char *endianness = NULL;
>> + CLEANUP_FREE char *end_elf_arch = NULL;
>> char *ret = NULL;
>>
>> /* Get the output of the "file" command. Note that because this
>> @@ -324,8 +330,10 @@ guestfs_impl_file_architecture (guestfs_h *g, const char
*path)
>> if (file == NULL)
>> return NULL;
>>
>> - if ((elf_arch = match1 (g, file, re_file_elf)) != NULL)
>> - ret = canonical_elf_arch (g, elf_arch);
>> + if ((match2 (g, file, re_file_elf, &endianness, &elf_arch)) != 0) {
>> + end_elf_arch = guestfs_int_safe_asprintf (g, "%s %s", endianness,
elf_arch);
>> + ret = canonical_elf_arch (g, end_elf_arch);
>> + }
> I still do think this approach, i.e. match MSB|LSB, create a new string
> with it and have it matched again, is doing the same thing twice for no
> reason.
>
> As I suggested in the v1 review, please do pass the result of the
> MSB|LSB match as new parameter for canonical_elf_arch, checking it
> when the architecture is ppc64. This will also avoid having a new regex,
> re_elf_ppc64le, and leave re_elf_ppc64 as it is currently:
>
> char *
> canonical_elf_arch (guestfs_h *g, const char *endianness,
> const char *elf_arch)
> {
> ...
> else if (match (g, elf_arch, re_elf_ppc64)) {
> if (STREQ (endianness, "LSB")
> r = "ppc64le";
> else
> r = "ppc64";
> }
> }
>
> No need for a new regex, and reuses the new MSB|LSB match as it is.
I don't like this because it creates more structured if/elseif that
needed and becomes more cluttered.
Considering the proposed changes to re_file_elf would already give
a MSB|LSB match, what would be the usefulness of forging a new
architecture string, different than either the file/magic output and
where you need to look for MSB|LSB *again*?
Passing the MSB|LSB match would allow also to check for different
architectures with different endianness (e.g. mips/mipsel), without
adding new regexps.
--
Pino Toscano