diff options
Diffstat (limited to 'rpath.c')
| -rw-r--r-- | rpath.c | 233 |
1 files changed, 233 insertions, 0 deletions
@@ -0,0 +1,233 @@ +#include "spm.h" + +/** + * Wrapper function to execute `patchelf` with arguments + * @param _filename Path of file to modify + * @param _args Arguments to pass to `patchelf` + * @return success=Process struct, failure=NULL + */ +Process *patchelf(const char *_filename, const char *_args) { + char *filename = strdup(_filename); + char *args = strdup(_args); + Process *proc_info = NULL; + char sh_cmd[PATH_MAX]; + sh_cmd[0] = '\0'; + + strchrdel(args, "&;|"); + strchrdel(filename, "&;|"); + sprintf(sh_cmd, "patchelf %s %s", args, filename); + + shell(&proc_info, SHELL_OUTPUT, sh_cmd); + + free(filename); + free(args); + return proc_info; +} + +/** + * Determine whether a RPATH or RUNPATH is present in file + * + * TODO: Replace with OS-native solution(s) + * + * @param _filename path to executable or library + * @return -1=OS error, 0=has rpath, 1=not found + */ +int has_rpath(const char *_filename) { + int result = 1; // default: not found + + char *filename = strdup(_filename); + if (!filename) { + return -1; + } + + Process *proc_info = NULL; + char *rpath = NULL; + + // sanitize input path + strchrdel(filename, "&;|"); + + Process *pe = patchelf(filename, "--print-rpath"); + strip(pe->output); + if (!isempty(pe->output)) { + result = 0; + } + else { + // something went wrong with patchelf other than + // what we're looking for + result = -1; + } + + free(filename); + shell_free(pe); + return result; +} + +/** + * Returns a RPATH or RUNPATH if one is defined in `_filename` + * + * TODO: Replace with OS-native solution(s) + * + * @param _filename path to executable or library + * @return RPATH string, NULL=error (caller is responsible for freeing memory) + */ +char *rpath_get(const char *_filename) { + if ((has_rpath(_filename)) != 0) { + return NULL; + } + char *filename = strdup(_filename); + if (!filename) { + return NULL; + } + char *path = strdup(filename); + if (!path) { + free(filename); + return NULL; + } + + Process *proc_info = NULL; + char *rpath = NULL; + + // sanitize input path + strchrdel(path, "&;|"); + + Process *pe = patchelf(filename, "--print-rpath"); + rpath = (char *)calloc(strlen(pe->output) + 1, sizeof(char)); + if (!rpath) { + free(filename); + free(path); + shell_free(pe); + return NULL; + } + strncpy(rpath, pe->output, strlen(pe->output)); + strip(rpath); + + free(filename); + free(path); + shell_free(pe); + return rpath; +} + +/** + * Generate a RPATH in the form of: + * + * `$ORIGIN/relative/path/to/lib/from/_filename/path` + * + * @param _filename + * @return + */ +char *rpath_generate(const char *_filename) { + const char *origin = "$ORIGIN/"; + char *filename = realpath(_filename, NULL); + if (!filename) { + return NULL; + } + char *nearest_lib = rpath_autodetect(filename); + if (!nearest_lib) { + return NULL; + } + char *result = (char *)calloc(strlen(origin) + strlen(nearest_lib) + 1, sizeof(char)); + if (!result) { + return NULL; + } + sprintf(result, "%s%s", origin, nearest_lib); + free(filename); + free(nearest_lib); + return result; +} + +int rpath_set(const char *filename, char *_rpath) { + int returncode; + + char *rpath_new = rpath_generate(filename); + if (!rpath_new) { + return -1; + } + + char *rpath_orig = rpath_get(filename); + if (!rpath_orig) { + return -1; + } + + // Are the original and new RPATH identical? + if (strcmp(rpath_orig, rpath_new) == 0) { + free(rpath_new); + free(rpath_orig); + return 0; + } + + Process *pe = patchelf(filename, "--set-rpath"); + if (pe) { + returncode = pe->returncode; + } + shell_free(pe); + free(rpath_new); + free(rpath_orig); + return pe->returncode; +} + +/** + * Using `filename` as a starting point, step backward through the filesystem looking for a lib directory + * @param filename path to file (or a directory) + * @return success=relative path from `filename` to nearest lib directory, failure=NULL + */ +char *rpath_autodetect(const char *filename) { + int has_real_libdir = 0; + char *rootdir = dirname(filename); + char *start = realpath(rootdir, NULL); + char *cwd = realpath(".", NULL); + char *result = NULL; + + // Change directory to the requested root + chdir(start); + + char visit[PATH_MAX]; // Current directory + char tmp[PATH_MAX]; // Current directory with lib directory appended + char relative[PATH_MAX]; // Generated relative path to lib directory + char sep[2]; // Holds the platform's directory separator + + // Initialize character arrays; + visit[0] = '\0'; + tmp[0] = '\0'; + relative[0] = '\0'; + sprintf(sep, "%c", DIRSEP); + + while(1) { + // Where are we in the file system? + getcwd(visit, sizeof(visit)); + // Using the current visit path, check if it contains a lib directory + sprintf(tmp, "%s%clib", visit, DIRSEP); + if (access(tmp, F_OK) == 0) { + strcat(relative, "lib"); + has_real_libdir = 1; // gate for memory allocation below + break; + } + // Reaching the top of the file system indicates our search for a lib directory failed + else if (strcmp(visit, "/") == 0) { + break; + } + + // Assemble relative path step for this location + strcat(relative, ".."); + strcat(relative, sep); + + // Step one directory level back + chdir(".."); + } + + // If we found a viable lib directory, allocate memory for it + if (has_real_libdir) { + result = (char *)calloc(strlen(relative) + 1, sizeof(char)); + if (!result) { + chdir(cwd); // return to calling directory + return NULL; + } + // Copy character array data to the result + strncpy(result, relative, strlen(relative)); + } + + chdir(cwd); // return to calling directory + free(rootdir); + free(cwd); + free(start); + return result; +} |