1 files changed, 106 insertions, 0 deletions
diff --git a/eprintf.c b/eprintf.c
new file mode 100644
index 0000000..7a885b3
--- /dev/null
+++ b/eprintf.c
@@ -0,0 +1,106 @@
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "eprintf.h"
+
+char *pname;
+
+/* eprintf: print error and exit, a trailing : in fmt prints strerror(errno) */
+void eprintf(const char *fmt, ...)
+{
+	int errnum = errno;
+	va_list va;
+
+	if (progname() != NULL)
+		fprintf(stderr, "%s: ", progname());
+
+	va_start(va, fmt);
+	vfprintf(stderr, fmt, va);
+	va_end(va);
+
+	if (fmt[0] != '\0' && fmt[strlen(fmt) - 1] == ':')
+		fprintf(stderr, " %s", strerror(errnum));
+	fputc('\n', stderr);
+
+	exit(EXIT_FAILURE);
+}
+
+/* weprintf: print warning, a trailing : in fmt prints strerror(errno) */
+void weprintf(const char *fmt, ...)
+{
+	int errnum = errno;
+	va_list va;
+
+	if (progname() != NULL)
+		fprintf(stderr, "%s: ", progname());
+
+	va_start(va, fmt);
+	vfprintf(stderr, fmt, va);
+	va_end(va);
+
+	if (fmt[0] != '\0' && fmt[strlen(fmt) - 1] == ':')
+		fprintf(stderr, " %s", strerror(errnum));
+	fputc('\n', stderr);
+}
+
+/* estrdup: attempt to strdup a string or exit on error */
+char *estrdup(const char *s)
+{
+	size_t len;
+	char *dup;
+
+	len = strlen(s);
+	if (len == SIZE_MAX)
+		eprintf("estrdup(\"%.20s\") failed: Too long", s);
+	dup = malloc(len + 1);
+	if (dup == NULL)
+		eprintf("estrdup(\"%.20s\") failed:", s);
+	strcpy(dup, s);
+
+	return dup;
+}
+
+/* emalloc: attempt to allocate memory or exit on error */
+void *emalloc(size_t n)
+{
+	void *p;
+
+	p = malloc(n);
+	if (p == NULL)
+		eprintf("emalloc(%zu) failed:", n);
+
+	return p;
+}
+
+/* erealloc: attempt to reallocate memory or exit on error */
+void *erealloc(void *p, size_t n)
+{
+	void *r;
+
+	r = realloc(p, n);
+	if (r == NULL)
+		eprintf("erealloc(%p, %zu) failed:", p, n);
+
+	return r;
+}
+
+/* progname: retrieve stored name of program */
+char *progname(void)
+{
+	return pname;
+}
+
+/* setprogname: set stored name of program */
+void setprogname(const char *s)
+{
+	if (pname != NULL) {
+		weprintf("setprogname(\"%.20s\") called more than once", s);
+		return;
+	}
+
+	pname = estrdup(s);
+}