Replace _dm_snprintf with EMIT_PARAMS macro for creating target lines

diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index c3861a09928080491cc869f3cbc4279fe9bf780f..cec8696907d76cab69478ccee25dce7c5693c922 100644 (file)
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
 Version 1.02.30 -
 ====================================
+  Replace _dm_snprintf with EMIT_PARAMS macro for creating target lines
 
 Version 1.02.29 - 10th November 2008
 ====================================

diff --git a/libdm/libdm-deptree.c b/libdm/libdm-deptree.c
index a101007c58fe0461b98f2a4b5613fd8c1f557326..d70e1b43a560182b110a2552a3fd21f9ad0125ce 100644 (file)
--- a/libdm/libdm-deptree.c
+++ b/libdm/libdm-deptree.c
@@ -135,22 +135,6 @@ struct dm_tree {
        int no_flush;           /* 1 sets noflush (mirrors/multipath) */
 };
 
-/* FIXME Consider exporting this */
-static int _dm_snprintf(char *buf, size_t bufsize, const char *format, ...)
-{
-        int n;
-        va_list ap;
-
-        va_start(ap, format);
-        n = vsnprintf(buf, bufsize, format, ap);
-        va_end(ap);
-
-        if (n < 0 || (n > (int) bufsize - 1))
-                return -1;
-
-        return n;
-}
-
 struct dm_tree *dm_tree_create(void)
 {
        struct dm_tree *dtree;
@@ -1238,27 +1222,32 @@ static int _build_dev_string(char *devbuf, size_t bufsize, struct dm_tree_node *
        return 1;
 }
 
+/* simplify string emiting code */
+#define EMIT_PARAMS(p, str...)\
+       do {\
+               const size_t bufsize = paramsize - (size_t)p;\
+               int w;\
+               \
+               if ((w = snprintf(params + p, bufsize, str)) < 0\
+                   || ((size_t)w >= bufsize)) {\
+                       stack; /* Out of space */\
+                       return -1;\
+               }\
+               p += w;\
+       } while (0)
+
 static int _emit_areas_line(struct dm_task *dmt __attribute((unused)),
                            struct load_segment *seg, char *params,
                            size_t paramsize, int *pos)
 {
        struct seg_area *area;
        char devbuf[DM_FORMAT_DEV_BUFSIZE];
-       int tw;
-       const char *prefix = "";
 
        dm_list_iterate_items(area, &seg->areas) {
                if (!_build_dev_string(devbuf, sizeof(devbuf), area->dev_node))
                        return_0;
 
-               if ((tw = _dm_snprintf(params + *pos, paramsize - *pos, "%s%s %" PRIu64,
-                                       prefix, devbuf, area->offset)) < 0) {
-                        stack; /* Out of space */
-                        return -1;
-                }
-
-               prefix = " ";
-               *pos += tw;
+               EMIT_PARAMS(*pos, " %s %" PRIu64, devbuf, area->offset);
        }
 
        return 1;
@@ -1267,9 +1256,8 @@ static int _emit_areas_line(struct dm_task *dmt __attribute((unused)),
 static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uint64_t *seg_start, char *params, size_t paramsize)
 {
        unsigned log_parm_count;
-        int pos = 0;
-       int tw;
-        int r;
+       int pos = 0;
+       int r;
        char originbuf[DM_FORMAT_DEV_BUFSIZE], cowbuf[DM_FORMAT_DEV_BUFSIZE];
        char logbuf[DM_FORMAT_DEV_BUFSIZE];
        const char *logtype;
@@ -1289,11 +1277,7 @@ static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uin
                if (seg->clustered) {
                        if (seg->uuid)
                                log_parm_count++;
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "clustered-")) < 0) {
-                               stack;  /* Out of space */
-                               return -1;
-                       }
-                       pos += tw;
+                       EMIT_PARAMS(pos, "clustered-");
                }
 
                if (!seg->log)
@@ -1305,61 +1289,25 @@ static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uin
                                return_0;
                }
 
-               if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s %u ", logtype, log_parm_count)) < 0) {
-                        stack; /* Out of space */
-                        return -1;
-                }
-               pos += tw;
-
-               if (seg->log) {
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s ", logbuf)) < 0) {
-                               stack;  /* Out of space */
-                               return -1;
-                       }
-                       pos += tw;
-               }
+               EMIT_PARAMS(pos, "%s %u", logtype, log_parm_count);
 
-               if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%u ", seg->region_size)) < 0) {
-                               stack; /* Out of space */
-                               return -1;
-                       }
-               pos += tw;
+               if (seg->log)
+                       EMIT_PARAMS(pos, " %s", logbuf);
 
-               if (seg->clustered && seg->uuid) {
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s ", seg->uuid)) < 0) {
-                               stack;  /* Out of space */
-                               return -1;
-                       }
-                       pos += tw;
-               }
+               EMIT_PARAMS(pos, " %u", seg->region_size);
 
-               if ((seg->flags & DM_NOSYNC)) {
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "nosync ")) < 0) {
-                                       stack; /* Out of space */
-                                       return -1;
-                               }
-                       pos += tw;
-               } else if ((seg->flags & DM_FORCESYNC)) {
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "sync ")) < 0) {
-                                       stack; /* Out of space */
-                                       return -1;
-                               }
-                       pos += tw;
-               }
+               if (seg->clustered && seg->uuid)
+                       EMIT_PARAMS(pos, " %s", seg->uuid);
 
-               if ((seg->flags & DM_BLOCK_ON_ERROR)) {
-                       if ((tw = _dm_snprintf(params + pos, paramsize - pos, "block_on_error ")) < 0) {
-                                       stack; /* Out of space */
-                                       return -1;
-                               }
-                       pos += tw;
-               }
+               if ((seg->flags & DM_NOSYNC))
+                       EMIT_PARAMS(pos, " nosync");
+               else if ((seg->flags & DM_FORCESYNC))
+                       EMIT_PARAMS(pos, " sync");
 
-               if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%u ", seg->mirror_area_count)) < 0) {
-                               stack; /* Out of space */
-                               return -1;
-                       }
-               pos += tw;
+               if ((seg->flags & DM_BLOCK_ON_ERROR))
+                       EMIT_PARAMS(pos, " block_on_error");
+
+               EMIT_PARAMS(pos, " %u", seg->mirror_area_count);
 
                break;
        case SEG_SNAPSHOT:
@@ -1367,30 +1315,16 @@ static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uin
                        return_0;
                if (!_build_dev_string(cowbuf, sizeof(cowbuf), seg->cow))
                        return_0;
-               if ((pos = _dm_snprintf(params, paramsize, "%s %s %c %d",
-                                        originbuf, cowbuf,
-                                       seg->persistent ? 'P' : 'N',
-                                        seg->chunk_size)) < 0) {
-                        stack; /* Out of space */
-                        return -1;
-                }
+               EMIT_PARAMS(pos, "%s %s %c %d", originbuf, cowbuf,
+                           seg->persistent ? 'P' : 'N', seg->chunk_size);
                break;
        case SEG_SNAPSHOT_ORIGIN:
                if (!_build_dev_string(originbuf, sizeof(originbuf), seg->origin))
                        return_0;
-               if ((pos = _dm_snprintf(params, paramsize, "%s",
-                                        originbuf)) < 0) {
-                        stack; /* Out of space */
-                        return -1;
-                }
+               EMIT_PARAMS(pos, "%s", originbuf);
                break;
        case SEG_STRIPED:
-               if ((pos = _dm_snprintf(params, paramsize, "%u %u ",
-                                         seg->area_count,
-                                         seg->stripe_size)) < 0) {
-                        stack; /* Out of space */
-                        return -1;
-                }
+               EMIT_PARAMS(pos, "%u %u", seg->area_count, seg->stripe_size);
                break;
        }
 
@@ -1421,6 +1355,8 @@ static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uin
        return 1;
 }
 
+#undef EMIT_PARAMS
+
 static int _emit_segment(struct dm_task *dmt, struct load_segment *seg,
                         uint64_t *seg_start)
 {