Extract filesystem-related functions into fs.c

[tinc] / src / fs.c

diff --git a/src/fs.c b/src/fs.c
new file mode 100644 (file)
index 0000000..772fa57
--- /dev/null
+++ b/src/fs.c
@@ -0,0 +1,142 @@
+#include "system.h"
+
+#include "fs.h"
+#include "names.h"
+#include "xalloc.h"
+
+static bool makedir(const char *path, mode_t mode) {
+       assert(path);
+
+       if(mkdir(path, mode)) {
+               if(errno == EEXIST) {
+                       chmod(path, mode);
+                       return true;
+               }
+
+               fprintf(stderr, "Could not create directory %s: %s\n", path, strerror(errno));
+               return false;
+       }
+
+       return true;
+}
+
+bool makedirs(tinc_dir_t dirs) {
+       if(!dirs) {
+               return false;
+       }
+
+       char path[PATH_MAX];
+       bool need_confbase = dirs & ~((unsigned)DIR_CONFDIR);
+
+       if(need_confbase && (!confbase || !makedir(confbase, 0755))) {
+               return false;
+       }
+
+       if(dirs & DIR_CONFDIR && !confbase_given && (!confdir || !makedir(confdir, 0755))) {
+               return false;
+       }
+
+       if(dirs & DIR_INVITATIONS) {
+               snprintf(path, sizeof(path), "%s" SLASH "invitations", confbase);
+
+               if(!makedir(path, 0700)) {
+                       return false;
+               }
+       }
+
+       if(dirs & DIR_CACHE) {
+               snprintf(path, sizeof(path), "%s" SLASH "cache", confbase);
+
+               if(!makedir(path, 0755)) {
+                       return false;
+               }
+       }
+
+       if(dirs & DIR_HOSTS) {
+               snprintf(path, sizeof(path), "%s" SLASH "hosts", confbase);
+
+               if(!makedir(path, 0755)) {
+                       return false;
+               }
+       }
+
+       return true;
+}
+
+
+/* Open a file with the desired permissions, minus the umask.
+   Also, if we want to create an executable file, we call fchmod()
+   to set the executable bits. */
+
+FILE *fopenmask(const char *filename, const char *mode, mode_t perms) {
+       mode_t mask = umask(0);
+       perms &= ~mask;
+       umask(~perms & 0777);
+       FILE *f = fopen(filename, mode);
+
+       if(!f) {
+               fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
+               return NULL;
+       }
+
+#ifdef HAVE_FCHMOD
+
+       if(perms & 0444) {
+               fchmod(fileno(f), perms);
+       }
+
+#endif
+       umask(mask);
+       return f;
+}
+
+char *absolute_path(const char *path) {
+#ifdef HAVE_WINDOWS
+       // Works for nonexistent paths
+       return _fullpath(NULL, path, 0);
+#else
+
+       if(!path || !*path) {
+               return NULL;
+       }
+
+       // If an absolute path was passed, return its copy
+       if(*path == '/') {
+               return xstrdup(path);
+       }
+
+       // Try using realpath. If it fails for any reason
+       // other than that the file was not found, bail out.
+       char *abs = realpath(path, NULL);
+
+       if(abs || errno != ENOENT) {
+               return abs;
+       }
+
+       // Since the file does not exist, we're forced to use a fallback.
+       // Get current working directory and concatenate it with the argument.
+       char cwd[PATH_MAX];
+
+       if(!getcwd(cwd, sizeof(cwd))) {
+               return NULL;
+       }
+
+       // Remove trailing slash if present since we'll be adding our own
+       size_t cwdlen = strlen(cwd);
+
+       if(cwdlen && cwd[cwdlen - 1] == '/') {
+               cwd[cwdlen - 1] = '\0';
+       }
+
+       // We don't do any normalization because it's complicated, and the payoff is small.
+       // If user passed something like '.././../foo' — that's their choice; fopen works either way.
+       xasprintf(&abs, "%s/%s", cwd, path);
+
+       if(strlen(abs) >= PATH_MAX) {
+               free(abs);
+               abs = NULL;
+       }
+
+       return abs;
+#endif
+}