Add QUtil::file_can_be_opened

This commit is contained in:
Jay Berkenbilt 2021-12-29 10:36:15 -05:00
parent ac0060ac38
commit af91b5b584
5 changed files with 29 additions and 18 deletions

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@ -1,3 +1,7 @@
2021-12-29 Jay Berkenbilt <ejb@ql.org>
* Add method QUtil::file_can_be_opened
2021-12-21 Jay Berkenbilt <ejb@ql.org>
* 10.5.0: release

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@ -111,6 +111,10 @@ namespace QUtil
QPDF_DLL
FILE* fopen_wrapper(std::string const&, FILE*);
// Attempt to open the file read only and then close again
QPDF_DLL
bool file_can_be_opened(char const* filename);
// Wrap around off_t versions of fseek and ftell if available
QPDF_DLL
int seek(FILE* stream, qpdf_offset_t offset, int whence);

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@ -515,6 +515,21 @@ QUtil::fopen_wrapper(std::string const& description, FILE* f)
return f;
}
bool
QUtil::file_can_be_opened(char const* filename)
{
try
{
fclose(safe_fopen(filename, "rb"));
return true;
}
catch (std::runtime_error&)
{
// can't open the file
}
return false;
}
int
QUtil::seek(FILE* stream, qpdf_offset_t offset, int whence)
{

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@ -203,6 +203,9 @@ void fopen_wrapper_test()
std::cout << "exception: " << s.what() << std::endl;
assert(s.getErrno() != 0);
}
assert(QUtil::file_can_be_opened("qutil.out"));
assert(! QUtil::file_can_be_opened("/does/not/exist"));
}
void getenv_test()

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@ -740,21 +740,6 @@ static void parse_object_id(std::string const& objspec,
}
}
static bool file_exists(char const* filename)
{
try
{
fclose(QUtil::safe_fopen(filename, "rb"));
return true;
}
catch (std::runtime_error&)
{
// can't open the file
}
return false;
}
// This is not a general-purpose argument parser. It is tightly
// crafted to work with qpdf. qpdf's command-line syntax is very
// complex because of its long history, and it doesn't really follow
@ -2976,7 +2961,7 @@ ArgParser::handleArgFileArguments()
argfile = 1 + argv[i];
if (strcmp(argfile, "-") != 0)
{
if (! file_exists(argfile))
if (! QUtil::file_can_be_opened(argfile))
{
// The file's not there; treating as regular option
argfile = nullptr;
@ -3276,7 +3261,7 @@ ArgParser::parsePagesOptions()
char const* file = argv[cur_arg++];
char const* password = 0;
char const* range = argv[cur_arg++];
if (! file_exists(file))
if (! QUtil::file_can_be_opened(file))
{
check_unclosed(file, 0);
}
@ -3315,7 +3300,7 @@ ArgParser::parsePagesOptions()
// "." means the input file.
QTC::TC("qpdf", "qpdf pages range omitted with .");
}
else if (file_exists(range))
else if (QUtil::file_can_be_opened(range))
{
QTC::TC("qpdf", "qpdf pages range omitted in middle");
// Yup, it's a file.