utils: add mkdir_recursive

[ppp.git] / pppd / utils.c

diff --git a/pppd/utils.c b/pppd/utils.c
index e75bb9c8eecd21279a999c18f8c0bc4f132ef1e3..c47192e67fef1a853830bb3d3ffd6885d756abbd 100644 (file)
--- a/pppd/utils.c
+++ b/pppd/utils.c
@@ -58,9 +58,10 @@
 #include <sys/mkdev.h>
 #endif
 
-#include "pppd.h"
+#include "pppd-private.h"
 #include "fsm.h"
 #include "lcp.h"
+#include "pathnames.h"
 
 
 #if defined(SUNOS4)
@@ -767,7 +768,7 @@ complete_read(int fd, void *buf, size_t count)
        for (done = 0; done < count; ) {
                nb = read(fd, ptr, count - done);
                if (nb < 0) {
-                       if (errno == EINTR && !got_sigterm)
+                       if (errno == EINTR && !ppp_signaled(SIGTERM))
                                continue;
                        return -1;
                }
@@ -780,19 +781,89 @@ complete_read(int fd, void *buf, size_t count)
 }
 #endif
 
-/* Procedures for locking the serial device using a lock file. */
-#ifndef LOCK_DIR
-#ifdef __linux__
-#define LOCK_DIR       "/var/lock"
-#else
-#ifdef SVR4
-#define LOCK_DIR       "/var/spool/locks"
-#else
-#define LOCK_DIR       "/var/spool/lock"
-#endif
-#endif
-#endif /* LOCK_DIR */
+/*
+ * mkdir_check - helper for mkdir_recursive, creates a directory
+ * but do not error on EEXIST if and only if entry is a directory
+ * The caller must check for errno == ENOENT if appropriate.
+ */
+static int
+mkdir_check(const char *path)
+{
+    struct stat statbuf;
+
+    if (mkdir(path, 0755) >= 0)
+       return 0;
 
+    if (errno == EEXIST) {
+       if (stat(path, &statbuf) < 0)
+           /* got raced? */
+           return -1;
+
+       if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
+           return 0;
+
+       /* already exists but not a dir, treat as failure */
+       errno = EEXIST;
+       return -1;
+    }
+
+    return -1;
+}
+
+/*
+ * mkdir_parent - helper for mkdir_recursive, modifies the string in place
+ * Assumes mkdir(path) already failed, so it first creates the parent then
+ * full path again.
+ */
+static int
+mkdir_parent(char *path)
+{
+    char *slash;
+    int rc;
+
+    slash = strrchr(path, '/');
+    if (!slash)
+       return -1;
+
+    *slash = 0;
+    if (mkdir_check(path) < 0) {
+       if (errno != ENOENT) {
+           *slash = '/';
+           return -1;
+       }
+       if (mkdir_parent(path) < 0) {
+           *slash = '/';
+           return -1;
+       }
+    }
+    *slash = '/';
+
+    return mkdir_check(path);
+}
+
+/*
+ * mkdir_recursive - recursively create directory if it didn't exist
+ */
+int
+mkdir_recursive(const char *path)
+{
+    char *copy;
+    int rc;
+
+    // optimistically try on full path first to avoid allocation
+    if (mkdir_check(path) == 0)
+       return 0;
+
+    copy = strdup(path);
+    if (!copy)
+       return -1;
+
+    rc = mkdir_parent(copy);
+    free(copy);
+    return rc;
+}
+
+/* Procedures for locking the serial device using a lock file. */
 static char lock_file[MAXPATHLEN];
 
 /*
@@ -833,7 +904,7 @@ lock(char *dev)
        return -1;
     }
     slprintf(lock_file, sizeof(lock_file), "%s/LK.%03d.%03d.%03d",
-            LOCK_DIR, major(sbuf.st_dev),
+            PPP_PATH_LOCKDIR, major(sbuf.st_dev),
             major(sbuf.st_rdev), minor(sbuf.st_rdev));
 #else
     char *p;
@@ -851,7 +922,7 @@ lock(char *dev)
        if ((p = strrchr(dev, '/')) != NULL)
            dev = p + 1;
 
-    slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", LOCK_DIR, dev);
+    slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", PPP_PATH_LOCKDIR, dev);
 #endif
 
     while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {