X-Git-Url: https://git.saurik.com/apple/libc.git/blobdiff_plain/3b2a1fe8d3d02703ddca1b0ead469074d4e47820..5b2abdfbf4211b6592cdd02b9507555a0ecbb04b:/gen/readdir_r.c?ds=inline

diff --git a/gen/readdir_r.c b/gen/readdir_r.c
new file mode 100644
index 0000000..8e19ccc
--- /dev/null
+++ b/gen/readdir_r.c
@@ -0,0 +1,51 @@
+#include <sys/types.h>
+#include <dirent.h>
+#include <pthread.h>
+
+/*
+ * Synopsis:
+ * dir_table is a global static array of pthread mutexes.  The array is NMUTEXES
+ * in length (NMUTEXES * sizeof(pthread_mutex_t)).
+ *
+ * Whenever a call to readdir_r is made, the element in the array indexed by the
+ * modulus of the file descriptor associated with dirp is locked, and readdir is
+ * called on dirp.  The result is returned in readdir_r semantics and the
+ * element in dir_table is unlocked.
+ */
+
+static pthread_mutex_t dir_table[]  = {
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER,
+	PTHREAD_MUTEX_INITIALIZER
+#define	NMUTEXES	8
+};
+
+int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
+{
+	int ret;
+	int mindex = dirp->dd_fd % NMUTEXES;
+	struct dirent *tmpdp;
+
+	pthread_mutex_lock(&dir_table[mindex]);
+
+	tmpdp = readdir(dirp);
+	if( tmpdp == NULL ) {
+		*result = NULL;
+		ret = errno;
+		pthread_mutex_unlock(&dir_table[mindex]);
+		return ret;
+	}
+
+	memcpy(entry, tmpdp, sizeof(struct dirent));
+	*result = entry;
+
+	pthread_mutex_unlock(&dir_table[mindex]);
+	return 0;
+}
+
+