Initial commit

2 files changed, 61 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..893f7b1
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+m4env
+*~
+\#*#
+.emacs*
+core
diff --git a/m4env.c b/m4env.c
new file mode 100644
index 0000000..0838e86
--- /dev/null
+++ b/m4env.c
@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <limits.h>
+#include <string.h>
+
+extern char **environ;
+
+char *progname;
+
+static void
+enomem(void)
+{
+	fprintf(stderr, "%s: not enough memory\n", progname);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	int xargc;
+	char **xargv;
+	int nenv, i, j;
+
+	progname = argv[0];
+	for (nenv = 0; environ[nenv]; nenv++)
+		;
+
+	if ((unsigned long) nenv + argc + 1 > INT_MAX) {
+		fprintf(stderr, "%s: environment size too big\n", progname);
+		return 1;
+	}
+
+	xargc = argc + nenv + 1;
+	xargv = calloc(xargc, sizeof(xargv[0]));
+	if (!xargv)
+		enomem();
+
+	xargv[0] = "m4";
+	for (i = 0; i < nenv; i++) {
+		size_t len;
+		char *def;
+
+		len = strlen(environ[i]) + 3;
+		if ((def = malloc(len)) == NULL)
+			enomem();
+		xargv[i + 1] = strcat(strcpy(def, "-D"), environ[i]);
+	}
+	for (j = 1; j <= argc; i++, j++)
+		xargv[i + 1] = argv[j];
+
+	execvp(xargv[0], xargv);
+	perror("execvp");
+	return 2;
+}
+