solaris fix attempt

Author: devnexen

main/io/php_io_copy_solaris.c

@@ -16,6 +16,7 @@
 
 #include "php_io_internal.h"
 #include <sys/types.h>
+#include <sys/stat.h>
 #include <sys/sendfile.h>
 #include <unistd.h>
 #include <errno.h>
@@ -31,22 +32,33 @@ static zend_result php_io_solaris_sendfile(int src_fd, int dest_fd, size_t maxle
 		return php_io_generic_copy_fallback(src_fd, dest_fd, maxlen, copied);
 	}
 
+	/* Unlike Linux, Solaris sendfile() returns -1/EINVAL (rather than 0) when
+	 * called with an offset at or past EOF, so a trailing call issued after the
+	 * source has been fully consumed would spuriously fail an otherwise complete
+	 * copy. Bound the loop to the bytes actually available in the source file so
+	 * we stop exactly at EOF and never call sendfile() past it. */
+	struct stat st;
+	if (fstat(src_fd, &st) != 0 || !S_ISREG(st.st_mode)) {
+		return php_io_generic_copy_fallback(src_fd, dest_fd, maxlen, copied);
+	}
+
+	size_t available = (st.st_size > start_offset) ? (size_t) (st.st_size - start_offset) : 0;
+	size_t target = (maxlen == PHP_IO_COPY_ALL || maxlen > available) ? available : maxlen;
+
 	off_t offset = start_offset;
 	size_t total_copied = 0;
-	size_t remaining = (maxlen == PHP_IO_COPY_ALL) ? SIZE_MAX : maxlen;
 	zend_result result = SUCCESS;
 
-	while (remaining > 0) {
+	while (total_copied < target) {
+		size_t remaining = target - total_copied;
 		size_t to_send = (remaining < SSIZE_MAX) ? remaining : SSIZE_MAX;
 		/* offset is updated in place by sendfile() */
 		ssize_t sent = sendfile(dest_fd, src_fd, &offset, to_send);
 
 		if (sent > 0) {
 			total_copied += (size_t) sent;
-			if (maxlen != PHP_IO_COPY_ALL) {
-				remaining -= (size_t) sent;
-			}
 		} else if (sent == 0) {
+			/* Source shrank under us; stop with what we have. */
 			break;
 		} else {
 			if (errno == EINTR) {