add dcm_filehandle_find_frame_number()

CHANGELOG.md

@@ -1,3 +1,10 @@
+## 1.3.0, date tbd
+
+* add dcm_filehandle_find_frame_number(), deprecate
+  dcm_filehandle_get_frame_number() [jcupitt]
+* add DCM_DEPRECATED() macro [jcupitt]
+* don't format ignored errors for debug log if logging is disabled [bgilbert]
+
 ## 1.2.1, 28/04/2026
 
 * add support for encapsulated pixel data reading [weanti]

include/dicom/dicom.h

@@ -20,6 +20,16 @@
 #define DCM_EXTERN __attribute__((visibility("default"))) extern
 #endif
 
+#ifndef BUILDING_LIBDICOM
+#if defined(_MSC_VER)
+#define DCM_DEPRECATED(MSG) __declspec(deprecated(MSG))
+#elif defined(__GNUC__)
+#define DCM_DEPRECATED(MSG) __attribute__((deprecated(MSG)))
+#endif
+#else
+#define DCM_DEPRECATED(MSG)
+#endif
+
 /**
  * Maximum number of characters in values with Value Representation AE.
  */
@@ -124,13 +134,7 @@ typedef struct _DcmSequence DcmSequence;
  * .. deprecated:: 1.1.0
  *    Calling this function is no longer necessary.
  */
-#ifndef BUILDING_LIBDICOM
-#if defined(_MSC_VER)
-__declspec(deprecated("dcm_init() no longer needs to be called"))
-#elif defined(__GNUC__)
-__attribute__((deprecated("dcm_init() no longer needs to be called")))
-#endif
-#endif
+DCM_DEPRECATED("dcm_init() no longer needs to be called")
 DCM_EXTERN
 void dcm_init(void);
 
@@ -1777,21 +1781,54 @@ DcmFrame *dcm_filehandle_read_frame(DcmError **error,
                                     DcmFilehandle *filehandle,
                                     uint32_t frame_number);
 
+/**
+ * Find the frame number at a position.
+ *
+ * Given a tile row and column, find the number of the frame that should be
+ * displayed at that position, taking into account any frame-positioning
+ * metadata.
+ *
+ * If no frame is available at that position, set frame_number to 0.
+ *
+ * :param error: Pointer to error object
+ * :param filehandle: File
+ * :param column: Column number, from 0
+ * :param row: Row number, from 0
+ * :param frame_number: Return one-based frame number, or 0 for no frame
+ *
+ * :return: true on success, false for error
+ */
+DCM_EXTERN
+bool dcm_filehandle_find_frame_number(DcmError **error,
+                                      DcmFilehandle *filehandle,
+                                      uint32_t column,
+                                      uint32_t row,
+                                      uint32_t *frame_number);
+
 /**
  * Get the frame number at a position.
  *
+ * Note: this function is deprecated, please use
+ * :c:func:`dcm_filehandle_find_frame_number()` instead.
+ *
  * Given a tile row and column, get the number of the frame that should be
  * displayed at that position, taking into account any frame-positioning
  * metadata.
  *
+ * If no frame is available, return false and set the error
+ * :c:enum:`DCM_ERROR_CODE_MISSING_FRAME`.
+ *
+ * frame_number may be NULL.
+ *
  * :param error: Pointer to error object
  * :param filehandle: File
  * :param column: Column number, from 0
  * :param row: Row number, from 0
  * :param frame_number: Return one-based frame number
  *
- * :return: true on success, false for no frame available
+ * :return: true on success, false for error or no frame available
  */
+DCM_DEPRECATED("deprecated for dcm_filehandle_find_frame_number()")
 DCM_EXTERN
 bool dcm_filehandle_get_frame_number(DcmError **error,
                                      DcmFilehandle *filehandle,

meson.build

@@ -10,7 +10,7 @@ project(
   ],
   license : 'MIT',
   meson_version : '>=0.55',
-  version : '1.2.1',
+  version : '1.3.0',
 )
 if not meson.is_subproject()
   meson.add_dist_script('scripts/dist.py')
@@ -34,8 +34,8 @@ endif
 #   2. Backward-compatible ABI change: bump minor, reset patch
 #   3. Other, eg. bugfix: bump patch
 abi_version_major = 1
-abi_version_minor = 2
-abi_version_patch = 1
+abi_version_minor = 3
+abi_version_patch = 0
 
 abi_version = '@0@.@1@.@2@'.format(
   abi_version_major,

src/dicom-file.c

@@ -1405,13 +1405,13 @@ DcmFrame *dcm_filehandle_read_frame(DcmError **error,
 }
 
 
-bool dcm_filehandle_get_frame_number(DcmError **error,
-                                     DcmFilehandle *filehandle,
-                                     uint32_t column,
-                                     uint32_t row,
-                                     uint32_t *frame_number)
+bool dcm_filehandle_find_frame_number(DcmError **error,
+                                      DcmFilehandle *filehandle,
+                                      uint32_t column,
+                                      uint32_t row,
+                                      uint32_t *frame_number)
 {
-    dcm_log_debug("Get frame number at (%u, %u)", column, row);
+    dcm_log_debug("Find frame number for tile (%u, %u)", column, row);
 
     if (!dcm_filehandle_prepare_read_frame(error, filehandle)) {
         return false;
@@ -1431,25 +1431,51 @@ bool dcm_filehandle_get_frame_number(DcmError **error,
     if (filehandle->layout == DCM_LAYOUT_SPARSE) {
         index = filehandle->frame_index[index];
         if (index == 0xffffffff) {
-            dcm_error_set(error, DCM_ERROR_CODE_MISSING_FRAME,
-                          "no frame",
-                          "no frame at position (%u, %u)", column, row);
-            return false;
+            // missing frame
+            *frame_number = 0;
+        }
+        else {
+            *frame_number = (uint32_t) (index + 1);
         }
     } else {
         // subtract the start of this file, for catenation support
         index -= filehandle->frame_offset;
         if (index < 0 || index >= (int64_t) filehandle->num_frames) {
-            dcm_error_set(error, DCM_ERROR_CODE_MISSING_FRAME,
-                          "no frame",
-                          "no frame at position (%u, %u)", column, row);
-            return false;
+            // missing frame
+            *frame_number = 0;
+        }
+        else {
+            *frame_number = (uint32_t) (index + 1);
         }
     }
 
-    // frame numbers are from 1, and are always uint32
+    return true;
+}
+
+
+/* Deprecated function, only here for compatibility with libdicom 1.2.
+ */
+bool dcm_filehandle_get_frame_number(DcmError **error,
+                                     DcmFilehandle *filehandle,
+                                     uint32_t column,
+                                     uint32_t row,
+                                     uint32_t *frame_number)
+{
+    uint32_t n;
+
+    if (!dcm_filehandle_find_frame_number(error, filehandle, column, row, &n)) {
+        return false;
+    }
+
+    if (n == 0) {
+        dcm_error_set(error, DCM_ERROR_CODE_MISSING_FRAME,
+                      "no frame",
+                      "no frame at position (%u, %u)", column, row);
+        return false;
+    }
+
     if (frame_number)
-        *frame_number = (uint32_t) (index + 1);
+        *frame_number = n;
 
     return true;
 }
@@ -1463,11 +1489,18 @@ DcmFrame *dcm_filehandle_read_frame_position(DcmError **error,
     dcm_log_debug("Read frame position (%u, %u)", column, row);
 
     uint32_t frame_number;
-    if (!dcm_filehandle_get_frame_number(error,
-            filehandle, column, row, &frame_number)) {
+    if (!dcm_filehandle_find_frame_number(error, filehandle,
+                                          column, row, &frame_number)) {
         return NULL;
     }
 
+    if (frame_number == 0) {
+        dcm_error_set(error, DCM_ERROR_CODE_MISSING_FRAME,
+                      "no frame",
+                      "no frame at position (%u, %u)", column, row);
+        return false;
+    }
+
     return dcm_filehandle_read_frame(error, filehandle, frame_number);
 }