Add a new function buffer_add_n(), and the corresponding

function-like macro OSRF_BUFFER_ADD_N.

These facilities append a specified number of characters from
an input string to a growing_buffer.  They are intended for
situations where the length of the input string is already known,
or where the input string is not nul-terminated in the right
place.

git-svn-id: svn://svn.open-ils.org/OpenSRF/trunk@1568 9efc2488-bf62-4759-914b-345cdb29e865

diff --git a/include/opensrf/utils.h b/include/opensrf/utils.h
index 91f4c2d..dd2be90 100644 (file)
--- a/include/opensrf/utils.h
+++ b/include/opensrf/utils.h
@@ -66,6 +66,21 @@ GNU General Public License for more details.
                }\
        } while(0)
 
+#define OSRF_BUFFER_ADD_N(gb, data, n) \
+       do {\
+               growing_buffer* gb__ = gb; \
+               const char* data__ = data; \
+               size_t n__ = n; \
+               if(gb__ && data__) {\
+                       int tl__ = n__ + gb__->n_used;\
+                       if( tl__ < gb__->size ) {\
+                               memcpy( gb__->buf + gb__->n_used, data__, n__ ); \
+                               gb__->buf[tl__] = '\0'; \
+                               gb__->n_used = tl__; \
+} else { buffer_add_n(gb__, data__, n__); }\
+}\
+} while(0)
+
 #define OSRF_BUFFER_ADD_CHAR(gb, c)\
        do {\
                if(gb) {\
@@ -193,6 +208,7 @@ growing_buffer* buffer_init( int initial_num_bytes);
 //int buffer_addchar(growing_buffer* gb, char c);
 
 int buffer_add(growing_buffer* gb, const char* c);
+int buffer_add_n(growing_buffer* gb, const char* data, size_t n);
 int buffer_fadd(growing_buffer* gb, const char* format, ... );
 int buffer_reset( growing_buffer* gb);
 char* buffer_data( const growing_buffer* gb);

diff --git a/src/libopensrf/utils.c b/src/libopensrf/utils.c
index 106463a..28d963a 100644 (file)
--- a/src/libopensrf/utils.c
+++ b/src/libopensrf/utils.c
@@ -247,6 +247,28 @@ int buffer_add(growing_buffer* gb, const char* data) {
        return total_len;
 }
 
+/** Append a specified number of characters to a growing_buffer.
+    If the characters so appended include an embedded nul, the results
+    are likely to be unhappy.
+*/
+int buffer_add_n(growing_buffer* gb, const char* data, size_t n) {
+       if(!(gb && data)) return 0;
+
+       if(n == 0) return 0;
+
+       int total_len = n + gb->n_used;
+
+       if( total_len >= gb->size ) {
+               if( buffer_expand( gb, total_len ) )
+                       return -1;
+       }
+
+       memcpy( gb->buf + gb->n_used, data, n );
+       gb->buf[total_len] = '\0';
+       gb->n_used = total_len;
+       return total_len;
+}
+
 
 int buffer_reset( growing_buffer *gb){
        if( gb == NULL ) { return -1; }