1 files changed, 143 insertions, 0 deletions
diff --git a/tools/xenstore/utils.c b/tools/xenstore/utils.c
new file mode 100644
index 0000000000..2345021f70
--- /dev/null
+++ b/tools/xenstore/utils.c
@@ -0,0 +1,143 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <signal.h>
+
+#include "utils.h"
+
+void xprintf(const char *fmt, ...)
+{
+        static FILE *out = NULL;
+        va_list args;
+        if (!out)
+                out = fopen("/dev/console", "w");
+	if (!out)
+		out = stderr;
+
+        va_start(args, fmt);
+        vfprintf(out, fmt, args);
+        va_end(args);
+        fflush(out);
+}
+
+void barf(const char *fmt, ...)
+{
+	char *str;
+	va_list arglist;
+
+	xprintf("FATAL: ");
+
+	va_start(arglist, fmt);
+	vasprintf(&str, fmt, arglist);
+	va_end(arglist);
+
+	xprintf("%s\n", str);
+	free(str);
+	exit(1);
+}
+
+void barf_perror(const char *fmt, ...)
+{
+	char *str;
+	int err = errno;
+	va_list arglist;
+
+	xprintf("FATAL: ");
+
+	va_start(arglist, fmt);
+	vasprintf(&str, fmt, arglist);
+	va_end(arglist);
+
+	xprintf("%s: %s\n", str, strerror(err));
+	free(str);
+	exit(1);
+}
+
+void *_realloc_array(void *ptr, size_t size, size_t num)
+{
+        if (num >= SIZE_MAX/size)
+                return NULL;
+        return realloc_nofail(ptr, size * num);
+}
+
+void *realloc_nofail(void *ptr, size_t size)
+{
+        ptr = realloc(ptr, size);
+	if (ptr)
+		return ptr;
+	barf("realloc of %zu failed", size);
+}
+
+void *malloc_nofail(size_t size)
+{
+	void *ptr = malloc(size);
+	if (ptr)
+		return ptr;
+	barf("malloc of %zu failed", size);
+}
+
+/* Stevens. */
+void daemonize(void)
+{
+	pid_t pid;
+
+	/* Separate from our parent via fork, so init inherits us. */
+	if ((pid = fork()) < 0)
+		barf_perror("Failed to fork daemon");
+	if (pid != 0)
+		exit(0);
+
+	close(STDIN_FILENO);
+	close(STDOUT_FILENO);
+	close(STDERR_FILENO);
+
+	/* Session leader so ^C doesn't whack us. */
+	setsid();
+	/* Move off any mount points we might be in. */
+	chdir("/");
+	/* Discard our parent's old-fashioned umask prejudices. */
+	umask(0);
+}
+
+
+/* This version adds one byte (for nul term) */
+void *grab_file(const char *filename, unsigned long *size)
+{
+	unsigned int max = 16384;
+	int ret, fd;
+	void *buffer;
+
+	if (streq(filename, "-"))
+		fd = dup(STDIN_FILENO);
+	else
+		fd = open(filename, O_RDONLY, 0);
+
+	if (fd < 0)
+		return NULL;
+
+	buffer = malloc(max+1);
+	*size = 0;
+	while ((ret = read(fd, buffer + *size, max - *size)) > 0) {
+		*size += ret;
+		if (*size == max)
+			buffer = realloc(buffer, max *= 2 + 1);
+	}
+	if (ret < 0) {
+		free(buffer);
+		buffer = NULL;
+	} else
+		((char *)buffer)[*size] = '\0';
+	close(fd);
+	return buffer;
+}
+
+void release_file(void *data, unsigned long size __attribute__((unused)))
+{
+	free(data);
+}