Verified Commit 0d7d83e5 authored by Tommaso Tocci's avatar Tommaso Tocci
Browse files

path resolution 

add support for path resolution, this will be used to get canonical path.

More info at `man path_resolution`
parent 039c07d0

ifs/include/global/path_util.hpp

+4 −2
Original line number Diff line number Diff line
@@ -6,13 +6,15 @@ 


#define PATH_MAX_LEN 4096 // 4k chars



constexpr char PSP = '/'; // PATH SEPARATOR





bool is_relative_path(const std::string& path);

bool is_absolute_path(const std::string& path);

bool has_trailing_slash(const std::string& path);



std::string path_to_relative(const std::string& root_path, const std::string& complete_path);

std::string prepend_path(const std::string& path, const char * raw_path);

std::string dirname(const std::string& path);

std::string get_current_working_dir();

std::vector<std::string> split_path(const std::string& path);



#endif //IFS_PATH_UTIL_HPP

ifs/include/preload/passthrough.hpp

+4 −0
Original line number Diff line number Diff line
@@ -92,6 +92,10 @@ extern void* libc_readdir; 
extern void* libc_closedir;



extern void* libc_chdir;

extern void* libc_fchdir;



extern void* libc_getcwd;

extern void* libc_get_current_dir_name;



extern void* libc_realpath;

ifs/include/preload/preload_context.hpp

+1 −1
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ class PreloadContext { 
    void cwd(const std::string& path);

    const std::string& cwd() const;



    bool relativize_path(std::string& path) const;

    bool relativize_path(const char * raw_path, std::string& relative_path) const;



    const std::shared_ptr<OpenFileMap>& file_map() const;

ifs/include/preload/resolve.hpp

0 → 100644
+5 −0
Original line number Diff line number Diff line 
#include <string>



bool resolve_path (const std::string& path, std::string& resolved);



std::string get_sys_cwd();

ifs/src/global/path_util.cpp

+45 −20
Original line number Diff line number Diff line 
#include <global/path_util.hpp>

#include <unistd.h>

#include <system_error>

#include <cstring>

#include <cassert>

#include <sys/stat.h>





const constexpr char PSP('/'); // PATH SEPARATOR



bool is_relative_path(const std::string& path) {

    return (!path.empty()) &&

           (path.front() != PSP);
@@ -20,6 +20,43 @@ bool has_trailing_slash(const std::string& path) { 
    return path.back() == PSP;

}



/* Add path prefix to a given C string.

 *

 * Returns a string composed by the `prefix_path`

 * followed by `raw_path`.

 *

 * This would return the same of:

 * ```

 * std::string(raw_path).append(prefix_path);

 * ```

 * But it is faster because it avoids to copy the `raw_path` twice.

 *

 *

 * Time cost approx: O(len(prefix_path)) + 2 O(len(raw_path))

 *

 * Example:

 * ```

 * prepend_path("/tmp/prefix", "./my/path") == "/tmp/prefix/./my/path"

 * ```

 */

std::string prepend_path(const std::string& prefix_path, const char * raw_path) {

    assert(!has_trailing_slash(prefix_path));

    std::size_t raw_len = std::strlen(raw_path);

    std::string res;

    res.reserve(prefix_path.size() + 1 + raw_len);

    res.append(prefix_path);

    res.push_back(PSP);

    res.append(raw_path, raw_len);

    return res;

}



/* Split a path into its components

 *

 * Returns a vector of the components of the given path.

 *

 * Example:

 *  split_path("/first/second/third") == ["first", "second", "third"]

 */

std::vector<std::string> split_path(const std::string& path) {

    std::vector<std::string> tokens;

    size_t start = std::string::npos;
@@ -35,6 +72,10 @@ std::vector<std::string> split_path(const std::string& path) { 
    return tokens;

}











/* Make an absolute path relative to a root path

 *

 * Convert @absolute_path into a relative one with respect to the given @root_path.
@@ -86,19 +127,3 @@ std::string dirname(const std::string& path) { 
    }

    return path.substr(0, parent_path_size);

}
 


std::string get_current_working_dir() {

    char temp[PATH_MAX_LEN];

    if(getcwd(temp, PATH_MAX_LEN) == NULL) {

        throw std::system_error(errno,

                                std::system_category(),

                                "Failed to retrieve current working directory");

    }

    // getcwd could return "(unreachable)<PATH>" in some cases

    if(temp[0] != '/') {

        throw std::runtime_error(

                "Current working directory is unreachable");

    }

    return {temp};

}