From 0720e8ef5c1d10373cd5faedd35eab2bc4e30fbf Mon Sep 17 00:00:00 2001
Message-Id: <0720e8ef5c1d10373cd5faedd35eab2bc4e30fbf.1716859790.git.mdw@distorted.org.uk>
From: Mark Wooding <mdw@chiark.greenend.org.uk>
Date: Sun, 17 Nov 2013 11:22:55 +0000
Subject: [PATCH] Sources, by analogy with sinks
Organization: Straylight/Edgeware

From: Richard Kettlewell <rjk@greenend.org.uk>

---
 lib/sink.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/sink.h | 23 +++++++++++++++++
 2 files changed, 95 insertions(+)

diff --git a/lib/sink.c b/lib/sink.c
index 152b7dc..0a3f701 100644
--- a/lib/sink.c
+++ b/lib/sink.c
@@ -227,6 +227,78 @@ struct sink *sink_socketio(struct socketio *sio) {
   return &s->s;
 }
 
+/* stdio source *************************************************************/
+
+/** @brief Source that reads from a socket handle */
+struct stdio_source {
+  /** @brief Base member */
+  struct source s;
+
+  FILE *fp;
+};
+
+static int source_stdio_getc(struct source *s) {
+  return getc(((struct stdio_source *)s)->fp);
+}
+
+static int source_stdio_error(struct source *s) {
+  FILE *fp = ((struct stdio_source *)s)->fp;
+  if(ferror(fp)) {
+#if _WIN32
+    return GetLastError();
+#else
+    return errno;
+#endif
+  }
+  return 0;
+}
+
+static int source_stdio_eof(struct source *s) {
+  FILE *fp = ((struct stdio_source *)s)->fp;
+  return feof(fp);
+}
+
+struct source *source_stdio(FILE *fp) {
+  struct stdio_source *ss = xmalloc(sizeof *ss);
+  ss->s.getch = source_stdio_getc;
+  ss->s.error = source_stdio_error;
+  ss->s.eof = source_stdio_eof;
+  ss->s.eclass = ec_errno;
+  ss->fp = fp;
+  return (struct source *)ss;
+}
+
+/* socket source ***********************************************************/
+
+/** @brief Source that reads from a socket handle */
+struct socket_source {
+  /** @brief Base member */
+  struct source s;
+
+  struct socketio *sio;
+};
+
+static int source_socketio_getc(struct source *s) {
+  return socketio_getc(((struct socket_source *)s)->sio);
+}
+
+static int source_socketio_error(struct source *s) {
+  return socketio_error(((struct socket_source *)s)->sio);
+}
+static int source_socketio_eof(struct source *s) {
+  return socketio_eof(((struct socket_source *)s)->sio);
+}
+
+struct source *source_socketio(struct socketio *sio) {
+  struct socket_source *ss = xmalloc(sizeof *ss);
+  ss->s.getch = source_socketio_getc;
+  ss->s.error = source_socketio_error;
+  ss->s.eof = source_socketio_eof;
+  ss->s.eclass = ec_native;
+  ss->sio = sio;
+  return (struct source *)ss;
+}
+
 /*
 Local Variables:
 c-basic-offset:2
diff --git a/lib/sink.h b/lib/sink.h
index ff763a6..fc99d6b 100644
--- a/lib/sink.h
+++ b/lib/sink.h
@@ -115,6 +115,29 @@ static inline int sink_err(struct sink *s) {
   return s->error(s);
 }
 
+struct source {
+  int (*getch)(struct source *s);
+  int (*error)(struct source *s);
+  int (*eof)(struct source *s);
+
+  enum error_class eclass;
+};
+
+struct source *source_stdio(FILE *fp);
+struct source *source_socketio(struct socketio *sio);
+
+static inline int source_getc(struct source *s) {
+  return s->getch(s);
+}
+
+static inline int source_err(struct source *s) {
+  return s->error(s);
+}
+
+static inline int source_eof(struct source *s) {
+  return s->eof(s);
+}
+
 #endif /* SINK_H */
 
 /*
-- 
[mdw]