From a15e8d92ea2ebc20abd54a7ecaa406f8e0de0c66 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Tue, 22 Oct 2019 16:01:02 +0100 Subject: libcamera: utils: Add a C++ dirname implementation Provide a std::string based implementation which conforms to the behaviour of the dirname() fucntion defined by POSIX. Tests are added to cover expected corner cases of the implementation. Signed-off-by: Kieran Bingham Reviewed-by: Laurent Pinchart --- src/libcamera/utils.cpp | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) (limited to 'src/libcamera/utils.cpp') diff --git a/src/libcamera/utils.cpp b/src/libcamera/utils.cpp index 453e3b3b..f566e88c 100644 --- a/src/libcamera/utils.cpp +++ b/src/libcamera/utils.cpp @@ -70,6 +70,54 @@ char *secure_getenv(const char *name) #endif } +/** + * \brief Identify the dirname portion of a path + * \param[in] path The full path to parse + * + * This function conforms with the behaviour of the %dirname() function as + * defined by POSIX. + * + * \return A string of the directory component of the path + */ +std::string dirname(const std::string &path) +{ + if (path.empty()) + return "."; + + /* + * Skip all trailing slashes. If the path is only made of slashes, + * return "/". + */ + size_t pos = path.size() - 1; + while (path[pos] == '/') { + if (!pos) + return "/"; + pos--; + } + + /* + * Find the previous slash. If the path contains no non-trailing slash, + * return ".". + */ + while (path[pos] != '/') { + if (!pos) + return "."; + pos--; + } + + /* + * Return the directory name up to (but not including) any trailing + * slash. If this would result in an empty string, return "/". + */ + while (path[pos] == '/') { + if (!pos) + return "/"; + pos--; + } + + return path.substr(0, pos + 1); +} + /** * \fn libcamera::utils::set_overlap(InputIt1 first1, InputIt1 last1, * InputIt2 first2, InputIt2 last2) -- cgit v1.2.1