pager: turn on "cat" optimization for DEFAULT_PAGER

diff --git a/pkt-line.c b/pkt-line.c
index 699c2dd3b9a60c147f71cd9e0a6f0e52c548c2f1..70f19501d0e0c0dd625976519fd039d5c7a8b314 100644 (file)
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "pkt-line.h"
 
+char packet_buffer[LARGE_PACKET_MAX];
 static const char *packet_trace_prefix = "git";
 static const char trace_key[] = "GIT_TRACE_PACKET";
 
@@ -103,13 +104,29 @@ void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
        strbuf_add(buf, buffer, n);
 }
 
-static int safe_read(int fd, void *buffer, unsigned size, int return_line_fail)
+static int get_packet_data(int fd, char **src_buf, size_t *src_size,
+                          void *dst, unsigned size, int options)
 {
-       ssize_t ret = read_in_full(fd, buffer, size);
-       if (ret < 0)
-               die_errno("read error");
-       else if (ret < size) {
-               if (return_line_fail)
+       ssize_t ret;
+
+       if (fd >= 0 && src_buf && *src_buf)
+               die("BUG: multiple sources given to packet_read");
+
+       /* Read up to "size" bytes from our source, whatever it is. */
+       if (src_buf && *src_buf) {
+               ret = size < *src_size ? size : *src_size;
+               memcpy(dst, *src_buf, ret);
+               *src_buf += ret;
+               *src_size -= ret;
+       } else {
+               ret = read_in_full(fd, dst, size);
+               if (ret < 0)
+                       die_errno("read error");
+       }
+
+       /* And complain if we didn't get enough bytes to satisfy the read. */
+       if (ret < size) {
+               if (options & PACKET_READ_GENTLE_ON_EOF)
                        return -1;
 
                die("The remote end hung up unexpectedly");
@@ -143,13 +160,14 @@ static int packet_length(const char *linelen)
        return len;
 }
 
-static int packet_read_internal(int fd, char *buffer, unsigned size, int return_line_fail)
+int packet_read(int fd, char **src_buf, size_t *src_len,
+               char *buffer, unsigned size, int options)
 {
        int len, ret;
        char linelen[4];
 
-       ret = safe_read(fd, linelen, 4, return_line_fail);
-       if (return_line_fail && ret < 0)
+       ret = get_packet_data(fd, src_buf, src_len, linelen, 4, options);
+       if (ret < 0)
                return ret;
        len = packet_length(linelen);
        if (len < 0)
@@ -161,50 +179,37 @@ static int packet_read_internal(int fd, char *buffer, unsigned size, int return_
        len -= 4;
        if (len >= size)
                die("protocol error: bad line length %d", len);
-       ret = safe_read(fd, buffer, len, return_line_fail);
-       if (return_line_fail && ret < 0)
+       ret = get_packet_data(fd, src_buf, src_len, buffer, len, options);
+       if (ret < 0)
                return ret;
+
+       if ((options & PACKET_READ_CHOMP_NEWLINE) &&
+           len && buffer[len-1] == '\n')
+               len--;
+
        buffer[len] = 0;
        packet_trace(buffer, len, 0);
        return len;
 }
 
-int packet_read(int fd, char *buffer, unsigned size)
+static char *packet_read_line_generic(int fd,
+                                     char **src, size_t *src_len,
+                                     int *dst_len)
 {
-       return packet_read_internal(fd, buffer, size, 1);
+       int len = packet_read(fd, src, src_len,
+                             packet_buffer, sizeof(packet_buffer),
+                             PACKET_READ_CHOMP_NEWLINE);
+       if (dst_len)
+               *dst_len = len;
+       return len ? packet_buffer : NULL;
 }
 
-int packet_read_line(int fd, char *buffer, unsigned size)
+char *packet_read_line(int fd, int *len_p)
 {
-       return packet_read_internal(fd, buffer, size, 0);
+       return packet_read_line_generic(fd, NULL, NULL, len_p);
 }
 
-int packet_get_line(struct strbuf *out,
-       char **src_buf, size_t *src_len)
+char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len)
 {
-       int len;
-
-       if (*src_len < 4)
-               return -1;
-       len = packet_length(*src_buf);
-       if (len < 0)
-               return -1;
-       if (!len) {
-               *src_buf += 4;
-               *src_len -= 4;
-               packet_trace("0000", 4, 0);
-               return 0;
-       }
-       if (*src_len < len)
-               return -2;
-
-       *src_buf += 4;
-       *src_len -= 4;
-       len -= 4;
-
-       strbuf_add(out, *src_buf, len);
-       *src_buf += len;
-       *src_len -= len;
-       packet_trace(out->buf, out->len, 0);
-       return len;
+       return packet_read_line_generic(-1, src, src_len, dst_len);
 }