pkt-line: add stdio packet write functions

This adds three new functions to pkt-line.c: packet_fwrite,
packet_fwrite_fmt and packet_fflush. Besides writing a pktline flush
packet, packet_fflush also flushes the stdio buffer of the stream.

Helped-by: Patrick Steinhardt <ps@pks.im>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jacob Vosmaer <jacob@gitlab.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/cache.h b/cache.h
index d23de693680196524283f85ce02d1cf6d32de160..011dac4eb75c4565686b265b64a651bcf476b1e9 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -1738,6 +1738,8 @@ extern const char *git_mailmap_blob;
 void maybe_flush_or_die(FILE *, const char *);
 __attribute__((format (printf, 2, 3)))
 void fprintf_or_die(FILE *, const char *fmt, ...);
+void fwrite_or_die(FILE *f, const void *buf, size_t count);
+void fflush_or_die(FILE *f);
 
 #define COPY_READ_ERROR (-2)
 #define COPY_WRITE_ERROR (-3)

diff --git a/pkt-line.c b/pkt-line.c
index 9f63eae2e643f7a70d23edccdb9944a12ff7cdad..de4a94b437e1d573ef9395314fbab2acfc38b887 100644 (file)
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -243,6 +243,43 @@ void packet_write(int fd_out, const char *buf, size_t size)
                die("%s", err.buf);
 }
 
+void packet_fwrite(FILE *f, const char *buf, size_t size)
+{
+       size_t packet_size;
+       char header[4];
+
+       if (size > LARGE_PACKET_DATA_MAX)
+               die(_("packet write failed - data exceeds max packet size"));
+
+       packet_trace(buf, size, 1);
+       packet_size = size + 4;
+
+       set_packet_header(header, packet_size);
+       fwrite_or_die(f, header, 4);
+       fwrite_or_die(f, buf, size);
+}
+
+void packet_fwrite_fmt(FILE *fh, const char *fmt, ...)
+{
+       static struct strbuf buf = STRBUF_INIT;
+       va_list args;
+
+       strbuf_reset(&buf);
+
+       va_start(args, fmt);
+       format_packet(&buf, "", fmt, args);
+       va_end(args);
+
+       fwrite_or_die(fh, buf.buf, buf.len);
+}
+
+void packet_fflush(FILE *f)
+{
+       packet_trace("0000", 4, 1);
+       fwrite_or_die(f, "0000", 4);
+       fflush_or_die(f);
+}
+
 void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
 {
        va_list args;

diff --git a/pkt-line.h b/pkt-line.h
index 5af5f456876841744f22bc67b8359e0a330ddc11..82b95e4bdd3b775ad6b75e4c5cea1e1cc704546e 100644 (file)
--- a/pkt-line.h
+++ b/pkt-line.h
@@ -35,6 +35,17 @@ int packet_write_fmt_gently(int fd, const char *fmt, ...) __attribute__((format
 int write_packetized_from_fd_no_flush(int fd_in, int fd_out);
 int write_packetized_from_buf_no_flush(const char *src_in, size_t len, int fd_out);
 
+/*
+ * Stdio versions of packet_write functions. When mixing these with fd
+ * based functions, take care to call fflush(3) before doing fd writes or
+ * closing the fd.
+ */
+void packet_fwrite(FILE *f, const char *buf, size_t size);
+void packet_fwrite_fmt(FILE *f, const char *fmt, ...) __attribute__((format (printf, 2, 3)));
+
+/* packet_fflush writes a flush packet and flushes the stdio buffer of f */
+void packet_fflush(FILE *f);
+
 /*
  * Read a packetized line into the buffer, which must be at least size bytes
  * long. The return value specifies the number of bytes read into the buffer.

diff --git a/write-or-die.c b/write-or-die.c
index d33e68f6abb30aed23d53909c1b855ad352a7baa..0b1ec8190b622d18751aef3d0e640bf3d0e63b97 100644 (file)
--- a/write-or-die.c
+++ b/write-or-die.c
@@ -70,3 +70,15 @@ void write_or_die(int fd, const void *buf, size_t count)
                die_errno("write error");
        }
 }
+
+void fwrite_or_die(FILE *f, const void *buf, size_t count)
+{
+       if (fwrite(buf, 1, count, f) != count)
+               die_errno("fwrite error");
+}
+
+void fflush_or_die(FILE *f)
+{
+       if (fflush(f))
+               die_errno("fflush error");
+}