I've written a getline(3) from scratch based on

https://manned.org/getdelim.3p and am happy for it to have whatever
licence nmh needs.

diff --git a/configure.ac b/configure.ac
index c778a15..b87dd64 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -96,7 +96,8 @@ dnl CHECK HEADER FILES
 dnl ------------------
 
 AC_HEADER_TIOCGWINSZ
 dnl ------------------
 
 AC_HEADER_TIOCGWINSZ

-AC_CHECK_HEADERS([fcntl.h wchar.h wctype.h sys/param.h sys/time.h sys/stream.h])
+AC_CHECK_HEADERS([fcntl.h stdbool.h wchar.h wctype.h \
+                  sys/param.h sys/time.h sys/stream.h])

 
 AC_CHECK_HEADER([sys/ptem.h], AC_DEFINE(WINSIZE_IN_PTEM,1,
   [Define to 1 if `struct winsize' requires <sys/ptem.h>.]),,
 
 AC_CHECK_HEADER([sys/ptem.h], AC_DEFINE(WINSIZE_IN_PTEM,1,
   [Define to 1 if `struct winsize' requires <sys/ptem.h>.]),,

diff --git a/sbr/getline.c b/sbr/getline.c
new file mode 100644 (file)
index 0000000..7e3e797
--- /dev/null
+++ b/sbr/getline.c
@@ -0,0 +1,86 @@
+/*
+ * getline.c -- replacement getline() implementation
+ *
+ * This code is Copyright (c) 2016, by the authors of nmh.  See the
+ * COPYRIGHT file in the root directory of the nmh distribution for
+ * complete copyright information.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <limits.h>
+#include <errno.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else  /* ! HAVE_STDBOOL_H */
+# define bool int
+# define true 1
+# define false 0
+#endif /* ! HAVE_STDBOOL_H */
+
+/* Largest possible size of buffer that allows SSIZE_MAX to be returned
+ * to indicate SSIZE_MAX - 1 characters read before the '\n'.  The
+ * additional 1 is for the terminating NUL. */
+#define MAX_AVAIL ((size_t)SSIZE_MAX + 1)
+
+/* Ideal increase in size of line buffer. */
+#define GROWTH 128
+
+ssize_t getline(char **lineptr, size_t *n, FILE *stream)
+{
+    char *l;
+    size_t avail;
+    size_t used;
+    int c;
+    bool last;
+
+    if (!lineptr || !n) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    l = *lineptr;
+    if (l)
+        avail = *n <= MAX_AVAIL ? *n : MAX_AVAIL;
+    else
+        avail = *n = 0; /* POSIX allows *lineptr = NULL, *n = 42. */
+    used = 0;
+    last = false;
+    for (;;) {
+        c = getc(stream);
+        if (c == EOF) {
+            if (ferror(stream) || /* errno set by stdlib. */
+                !used)            /* EOF with nothing read. */
+                return -1;
+            /* Line will be returned without a \n terminator. */
+append_nul:
+            c = '\0';
+            last = true;
+        }
+
+        if (used == avail) {
+            size_t want;
+            char *new;
+
+            if (avail == MAX_AVAIL) {
+                errno = EOVERFLOW;
+                return -1;
+            }
+            want = avail + GROWTH;
+            if (want > MAX_AVAIL)
+                want = MAX_AVAIL;
+            new = realloc(l, want);
+            if (!new)
+                return -1; /* errno set by stdlib. */
+            l = *lineptr = new;
+            avail = *n = want;
+        }
+        l[used++] = c;
+
+        if (last)
+            return used - 1; /* Don't include NUL. */
+
+        if (c == '\n')
+            goto append_nul; /* Final half loop. */
+    }
+}