1 files changed, 105 insertions, 0 deletions
diff --git a/libmultipath/callout.c b/libmultipath/callout.c
new file mode 100644
index 0000000..f891a69
--- /dev/null
+++ b/libmultipath/callout.c
@@ -0,0 +1,105 @@
+#include <stdio.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <errno.h>
+
+#define PROGRAM_SIZE	100
+#define FIELD_PROGRAM
+
+#define strfieldcpy(to, from) \
+do { \
+	to[sizeof(to)-1] = '\0'; \
+	strncpy(to, from, sizeof(to)-1); \
+} while (0)
+
+int execute_program(char *path, char *value, int len)
+{
+	int retval;
+	int count;
+	int status;
+	int fds[2];
+	pid_t pid;
+	char *pos;
+	char arg[PROGRAM_SIZE];
+	char *argv[sizeof(arg) / 2];
+	int i;
+
+	i = 0;
+
+	if (strchr(path, ' ')) {
+		strfieldcpy(arg, path);
+		pos = arg;
+		while (pos != NULL) {
+			if (pos[0] == '\'') {
+				/* don't separate if in apostrophes */
+				pos++;
+				argv[i] = strsep(&pos, "\'");
+				while (pos[0] == ' ')
+					pos++;
+			} else {
+				argv[i] = strsep(&pos, " ");
+			}
+			i++;
+		}
+	} else {
+		argv[i++] = path;
+	}
+	argv[i] =  NULL;
+
+	retval = pipe(fds);
+
+	if (retval != 0)
+		return -1;
+
+
+	pid = fork();
+
+	switch(pid) {
+	case 0:
+		/* child */
+		close(STDOUT_FILENO);
+
+		/* dup write side of pipe to STDOUT */
+		dup(fds[1]);
+
+		retval = execv(argv[0], argv);
+
+		exit(-1);
+	case -1:
+		return -1;
+	default:
+		/* parent reads from fds[0] */
+		close(fds[1]);
+		retval = 0;
+		i = 0;
+		while (1) {
+			count = read(fds[0], value + i, len - i-1);
+			if (count <= 0)
+				break;
+
+			i += count;
+			if (i >= len-1) {
+				retval = -1;
+				break;
+			}
+		}
+
+		if (count < 0)
+			retval = -1;
+
+		if (i > 0 && value[i-1] == '\n')
+			i--;
+		value[i] = '\0';
+
+		wait(&status);
+		close(fds[0]);
+
+		if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
+			retval = -1;
+	}
+	return retval;
+}