More information is at http://code.neil.williamsleesmill.me.uk/
Each foreach function uses g_return_if_fail checks to protect the target book. If any essential data is missing, the loop returns without changing the target book. Note that this will not set or return an error value. However, g_return is only used for critical errors that arise from programming errors, not for invalid import data which should be cleaned up before creating the import QofBook.
Only qof_book_merge_update_result and qof_book_merge_commit return any error values to the calling process. qof_book_merge_init returns a pointer to the QofBookMergeData struct - the calling process needs to make sure this is non-NULL to know that the Init has been successful.
Files | |
file | qofbookmerge.h |
API for merging two QofBook structures with collision handling. | |
Data Structures | |
struct | QofBookMergeRule |
One rule per entity, built into a single GList for the entire merge. More... | |
struct | QofBookMergeData |
mergeData contains the essential context data for any merge. More... | |
qof_book_merge API | |
typedef void(* | QofBookMergeRuleForeachCB )(QofBookMergeData *, QofBookMergeRule *, guint) |
Definition of the dialogue control callback routine. | |
QofBookMergeData * | qof_book_merge_init (QofBook *importBook, QofBook *targetBook) |
Initialise the QofBookMerge process. | |
void | qof_book_merge_rule_foreach (QofBookMergeData *mergeData, QofBookMergeRuleForeachCB callback, QofBookMergeResult mergeResult) |
Dialogue Control Callback. | |
gchar * | qof_book_merge_param_as_string (QofParam *qtparam, QofEntity *qtEnt) |
provides easy string access to parameter data for dialogue use | |
QofBookMergeData * | qof_book_merge_update_result (QofBookMergeData *mergeData, QofBookMergeResult tag) |
called by dialogue callback to set the result of user intervention | |
gint | qof_book_merge_commit (QofBookMergeData *mergeData) |
Commits the import data to the target book. | |
void | qof_book_merge_abort (QofBookMergeData *mergeData) |
Abort the merge and free all memory allocated by the merge. | |
Enumerations | |
enum | QofBookMergeResult { MERGE_UNDEF, MERGE_ABSOLUTE, MERGE_NEW, MERGE_REPORT, MERGE_DUPLICATE, MERGE_UPDATE, MERGE_INVALID } |
Results of collisions and user resolution. More... |
typedef void(* QofBookMergeRuleForeachCB)(QofBookMergeData *, QofBookMergeRule *, guint) |
Definition of the dialogue control callback routine.
All MERGE_REPORT rules must be offered for user intervention using this template.
Commit will fail if any rules are still tagged as MERGE_REPORT.
Calling processes are free to also offer MERGE_NEW, MERGE_UPDATE, MERGE_DUPLICATE and MERGE_ABSOLUTE for user intervention. Attempting to query MERGE_INVALID rules will cause an error.
For an example, consider test_rule_loop, declared as:
void test_rule_loop(QofBookMergeData *mergeData, QofBookMergeRule *rule, guint remainder);
void test_rule_loop(QofBookMergeData *mergeData, QofBookMergeRule *rule, guint remainder)
{
g_return_if_fail(rule != NULL);
g_return_if_fail(mergeData != NULL); printf("Rule Result %s", rule->mergeType);
qof_book_merge_update_result(mergeData, rule, MERGE_UPDATE);
}
The dialogue is free to call qof_book_merge_update_result in the loop or at the end as long as the link between the rule and the result is maintained, e.g. by using a GHashTable.
The parameters are:
If the dialogue sets any rule result to MERGE_INVALID, the import will abort when qof_book_merge_commit is called. It is the responsibility of the calling function to handle the error code from qof_book_merge_commit, close the dialogue and return. The merge routines in these files will already have halted the merge operation and freed any memory allocated to merge structures before returning the error code. There is no need for the dialogue process to report back to QofBookMerge in this situation.
Definition at line 321 of file qofbookmerge.h.
enum QofBookMergeResult |
Results of collisions and user resolution.
All rules are initialised as MERGE_UNDEF. Once the comparison is complete, each object within the import will be updated.
MERGE_ABSOLUTE, MERGE_NEW, MERGE_DUPLICATE and MERGE_UPDATE can be reported to the user along with all MERGE_REPORT objects for confirmation. It may be useful later to allow MERGE_ABSOLUTE, MERGE_NEW, MERGE_DUPLICATE and MERGE_UPDATE to not be reported, if the user sets a preferences option for each result. (Always accept new items: Y/N default NO, ignores all MERGE_NEW if set to Y etc.) This option would not require any changes to qofbookmerge.
MERGE_NEW, MERGE_DUPLICATE and MERGE_UPDATE are only actioned after conflicts are resolved by the user using a dialog and all MERGE_REPORT objects are re-assigned to one of MERGE_NEW, MERGE_DUPLICATE or MERGE_UPDATE. There is no automatic merge, even if no entities are tagged as MERGE_REPORT, the calling process must still check for REPORT items using qof_book_merge_rule_foreach and call qof_book_merge_commit.
MERGE_INVALID data should be rare and allows for user-abort - the imported file/source may be corrupted and the prescence of invalid data should raise concerns that the rest of the data may be corrupted, damaged or otherwise altered. If any entity is tagged as MERGE_INVALID, the merge operation will abort and leave the target book completely unchanged.
MERGE_ABSOLUTE is only used for a complete match. The import object contains the same data in the same parameters with no omissions or amendments. If any data is missing, amended or added, the data is labelled MERGE_UPDATE.
Every piece of data has a corresponding result. Only when the count of items labelled MERGE_REPORT is equal to zero are MERGE_NEW and MERGE_UPDATE items added to the existing book.
MERGE_DUPLICATE items are silently ignored. Aborting the dialogue/process (by the user or in a program crash) at any point before the final commit leaves the existing book completely untouched.
Definition at line 125 of file qofbookmerge.h.
00126 { 00127 MERGE_UNDEF, 00128 MERGE_ABSOLUTE, 00129 MERGE_NEW, 00131 MERGE_REPORT, 00132 MERGE_DUPLICATE, 00134 MERGE_UPDATE, 00136 MERGE_INVALID 00138 } QofBookMergeResult;
void qof_book_merge_abort | ( | QofBookMergeData * | mergeData | ) |
Abort the merge and free all memory allocated by the merge.
Sometimes, setting MERGE_INVALID is insufficient: e.g. if the user aborts the merge from outside the functions dealing with the merge ruleset. This function causes an immediate abort - the calling process must start again at Init if a new merge is required.
Definition at line 1024 of file qofbookmerge.c.
01027 { 01028 param_string = qtparam->param_getfcn (qtEnt, qtparam); 01029 if (param_string == NULL) 01030 param_string = ""; 01031 return param_string; 01032 } 01033 if (safe_strcmp (paramType, QOF_TYPE_TIME) == 0) 01034 { 01035 QofDate *qd; 01036 01037 param_qt = qof_time_copy ( 01038 qtparam->param_getfcn (qtEnt, qtparam)); 01039 if (!param_qt) 01040 return NULL; 01041 qd = qof_date_from_qtime (param_qt); 01042 param_string = qof_date_print (qd, QOF_DATE_FORMAT_UTC); 01043 qof_date_free (qd); 01044 qof_time_free (param_qt); 01045 return param_string; 01046 } 01047 #ifndef QOF_DISABLE_DEPRECATED 01048 if (safe_strcmp (paramType, QOF_TYPE_DATE) == 0) 01049 { 01050 Timespec param_ts, (*date_getter) (QofEntity *, QofParam *);
gint qof_book_merge_commit | ( | QofBookMergeData * | mergeData | ) |
Commits the import data to the target book.
The last function in the API and the final part of any QofBookMerge operation.
qof_book_merge_commit will abort the entire merge operation if any rule is set to MERGE_INVALID. It is the responsibility of the calling function to handle the error code from qof_book_mergeCommit, close the dialogue and return. qof_book_merge_commit will already have halted the merge operation and freed any memory allocated to all merge structures before returning the error code. There is no way for the dialogue process to report back to qof_book_merge in this situation.
qof_book_merge_commit checks for any entities still tagged as MERGE_REPORT and then proceeds to import all entities tagged as MERGE_UPDATE or MERGE_NEW into the target book.
This final process cannot be UNDONE!
mergeData | the merge context, QofBookMergeData* |
Definition at line 1218 of file qofbookmerge.c.
01218 { 01219 struct QofBookMergeRuleIterate qiter; 01220 QofBookMergeRule *currentRule; 01221 GList *matching_rules, *node; 01222 01223 g_return_if_fail (cb != NULL); 01224 g_return_if_fail (mergeData != NULL); 01225 currentRule = mergeData->currentRule; 01226 g_return_if_fail (mergeResult > 0); 01227 g_return_if_fail (mergeResult != MERGE_INVALID); 01228 g_return_if_fail (mergeData->abort == FALSE); 01229 qiter.fcn = cb; 01230 qiter.data = mergeData; 01231 matching_rules = NULL; 01232 for (node = mergeData->mergeList; node != NULL; node = node->next) 01233 { 01234 currentRule = node->data; 01235 if (currentRule->mergeResult == mergeResult) 01236 matching_rules = g_list_prepend (matching_rules, 01237 currentRule); 01238 } 01239 qiter.remainder = g_list_length (matching_rules); 01240 g_list_foreach (matching_rules, qof_book_merge_rule_cb, &qiter); 01241 g_list_free (matching_rules); 01242 } 01243 01244 /* ============================================================== */ 01245 /* ============================================================== */
QofBookMergeData* qof_book_merge_init | ( | QofBook * | importBook, | |
QofBook * | targetBook | |||
) |
Initialise the QofBookMerge process.
First function of the QofBookMerge API. Every merge must begin with init.
Requires the book to import (QofBook *) and the book to receive the import, the target book (QofBook *). Returns a pointer to QofBookMergeData which must be checked for a NULL before continuing.
Process:
Definition at line 987 of file qofbookmerge.c.
01000 : 2005-01-01T10:55:23Z 01001 If you change QOF_UTC_DATE_FORMAT, change 01002 backend/file/qsf-xml.c : qsf_entity_foreach to 01003 reformat to QSF_XSD_TIME or the QSF XML will 01004 FAIL the schema validation and QSF exports will become invalid. 01005 01006 The QOF_TYPE_BOOLEAN is lowercase for the same reason. 01007 */ 01009 gchar * 01010 qof_book_merge_param_as_string (QofParam * qtparam, QofEntity * qtEnt) 01011 { 01012 gchar *param_string; 01013 gchar param_sa[GUID_ENCODING_LENGTH + 1]; 01014 QofType paramType; 01015 const GUID *param_guid; 01016 QofTime *param_qt; 01017 QofNumeric param_numeric, (*numeric_getter) (QofEntity *, QofParam *); 01018 gdouble param_double, (*double_getter) (QofEntity *, QofParam *); 01019 gboolean param_boolean, (*boolean_getter) (QofEntity *, QofParam *); 01020 gint32 param_i32, (*int32_getter) (QofEntity *, QofParam *); 01021 gint64 param_i64, (*int64_getter) (QofEntity *, QofParam *);
provides easy string access to parameter data for dialogue use
Uses the param_getfcn to retrieve the parameter value as a string, suitable for display in dialogues and user intervention output. Within a QofBookMerge context, only the parameters used in the merge are available, i.e. parameters where both param_getfcn and param_setfcn are not NULL.
Note that the object type description (a full text version of the object name) is also available to the dialogue as QofBookMergeRule::mergeLabel.
This allows the dialog to display the description of the object and all parameter data.
Definition at line 1064 of file qofbookmerge.c.
01066 { 01067 numeric_getter = 01068 (QofNumeric (*)(QofEntity *, 01069 QofParam *)) qtparam->param_getfcn; 01070 param_numeric = numeric_getter (qtEnt, qtparam); 01071 param_string = g_strdup (qof_numeric_to_string (param_numeric)); 01072 return param_string; 01073 } 01074 if (safe_strcmp (paramType, QOF_TYPE_GUID) == 0) 01075 { 01076 param_guid = qtparam->param_getfcn (qtEnt, qtparam); 01077 guid_to_string_buff (param_guid, param_sa); 01078 param_string = g_strdup (param_sa); 01079 return param_string; 01080 } 01081 if (safe_strcmp (paramType, QOF_TYPE_INT32) == 0) 01082 { 01083 int32_getter = 01084 (gint32 (*)(QofEntity *, QofParam *)) qtparam->param_getfcn; 01085 param_i32 = int32_getter (qtEnt, qtparam); 01086 param_string = g_strdup_printf ("%d", param_i32); 01087 return param_string; 01088 } 01089 if (safe_strcmp (paramType, QOF_TYPE_INT64) == 0) 01090 { 01091 int64_getter = 01092 (gint64 (*)(QofEntity *, QofParam *)) qtparam->param_getfcn; 01093 param_i64 = int64_getter (qtEnt, qtparam); 01094 param_string = g_strdup_printf ("%" G_GINT64_FORMAT, param_i64); 01095 return param_string; 01096 } 01097 if (safe_strcmp (paramType, QOF_TYPE_DOUBLE) == 0) 01098 { 01099 double_getter = 01100 (double (*)(QofEntity *, QofParam *)) qtparam->param_getfcn; 01101 param_double = double_getter (qtEnt, qtparam); 01102 param_string = g_strdup_printf ("%f", param_double); 01103 return param_string; 01104 } 01105 if (safe_strcmp (paramType, QOF_TYPE_BOOLEAN) == 0) 01106 { 01107 boolean_getter = 01108 (gboolean (*)(QofEntity *, QofParam *)) qtparam->param_getfcn; 01109 param_boolean = boolean_getter (qtEnt, qtparam); 01110 /* Boolean values need to be lowercase for QSF validation. */ 01111 if (param_boolean == TRUE) 01112 param_string = g_strdup ("true"); 01113 else 01114 param_string = g_strdup ("false"); 01115 return param_string; 01116 } 01117 /* "kvp" contains repeating values, cannot be a single string for the frame. */ 01118 if (safe_strcmp (paramType, QOF_TYPE_KVP) == 0) 01119 return param_string; 01120 if (safe_strcmp (paramType, QOF_TYPE_CHAR) == 0) 01121 { 01122 char_getter = 01123 (gchar (*)(QofEntity *, QofParam *)) qtparam->param_getfcn; 01124 param_char = char_getter (qtEnt, qtparam); 01125 param_string = g_strdup_printf ("%c", param_char); 01126 return param_string; 01127 } 01128 return NULL; 01129 } 01130 01131 QofBookMergeData * 01132 qof_book_merge_update_result (QofBookMergeData * mergeData, 01133 QofBookMergeResult tag) 01134 { 01135 QofBookMergeRule *resolved; 01136 01137 g_return_val_if_fail ((mergeData != NULL), NULL); 01138 g_return_val_if_fail ((tag > 0), NULL); 01139 g_return_val_if_fail ((tag != MERGE_REPORT), NULL); 01140 resolved = mergeData->currentRule; 01141 g_return_val_if_fail ((resolved != NULL), NULL); 01142 if ((resolved->mergeAbsolute == TRUE) && (tag == MERGE_DUPLICATE)) 01143 tag = MERGE_ABSOLUTE; 01144 if ((resolved->mergeAbsolute == TRUE) && (tag == MERGE_NEW)) 01145 tag = MERGE_UPDATE; 01146 if ((resolved->mergeAbsolute == FALSE) && (tag == MERGE_ABSOLUTE)) 01147 tag = MERGE_DUPLICATE; 01148 if ((resolved->mergeResult == MERGE_NEW) && (tag == MERGE_UPDATE)) 01149 tag = MERGE_NEW; 01150 if (resolved->updated == FALSE) 01151 resolved->mergeResult = tag; 01152 resolved->updated = TRUE; 01153 if (tag >= MERGE_INVALID) 01154 { 01155 mergeData->abort = TRUE; 01156 mergeData->currentRule = resolved; 01157 return NULL; 01158 } 01159 mergeData->currentRule = resolved; 01160 return mergeData; 01161 } 01162 01163 gint 01164 qof_book_merge_commit (QofBookMergeData * mergeData) 01165 { 01166 QofBookMergeRule *currentRule; 01167 GList *check, *node; 01168 01169 g_return_val_if_fail (mergeData != NULL, -1); 01170 g_return_val_if_fail (mergeData->mergeList != NULL, -1); 01171 g_return_val_if_fail (mergeData->targetBook != NULL, -1); 01172 if (mergeData->abort == TRUE) 01173 return -1; 01174 check = g_list_copy (mergeData->mergeList); 01175 g_return_val_if_fail (check != NULL, -1); 01176 for (node = check; node != NULL; node = node->next) 01177 { 01178 currentRule = node->data; 01179 if (currentRule->mergeResult == MERGE_INVALID) 01180 { 01181 qof_book_merge_abort (mergeData); 01182 g_list_free (check); 01183 return (-2);
void qof_book_merge_rule_foreach | ( | QofBookMergeData * | mergeData, | |
QofBookMergeRuleForeachCB | callback, | |||
QofBookMergeResult | mergeResult | |||
) |
Dialogue Control Callback.
This function is designed to be used to iterate over all rules tagged with a specific QofBookMergeResult value.
callback | external loop of type QofBookMergeRuleForeachCB | |
mergeResult | QofBookMergeResult value to look up. | |
mergeData | QofBookMergeData merge context. |
Uses qof_book_get_collection with the QofBookMergeRule::mergeType object type to return a collection of QofEntity entities from either the QofBookMergeData::mergeBook or QofBookMergeData::targetBook. Then uses qof_collection_lookup_entity to lookup the QofBookMergeRule::importEnt and again the qof_book_mergeRule::targetEnt to return the two specific entities.
Definition at line 1270 of file qofbookmerge.c.
QofBookMergeData* qof_book_merge_update_result | ( | QofBookMergeData * | mergeData, | |
QofBookMergeResult | tag | |||
) |
called by dialogue callback to set the result of user intervention
Set any rule result to MERGE_INVALID to abort the import when qof_book_merge_commit is called, without changing the target book.
The calling process should make it absolutely clear that a merge operation cannot be undone and that a backup copy should always be available before a merge is initialised.
Recommended method: Only offer three options to the user per rule:
Handle the required result changes in code: Check the value of qof_book_mergeRule::mergeAbsolute and use these principles:
To ignore entities tagged as:
To merge entities that are not pre-set to MERGE_NEW, set MERGE_UPDATE.
Attempting to merge an entity when the pre-set value was MERGE_NEW will force a change back to MERGE_NEW because no suitable target exists for the merge.
To add entities, check mergeAbsolute is FALSE and set MERGE_NEW.
An entity only be added if mergeAbsolute is FALSE. Attempting to add an entity when mergeAbsolute is TRUE will always force a MERGE_UPDATE.
It is not possible to update the same rule more than once.
qof_book_merge_commit only commits entities tagged with MERGE_NEW and MERGE_UPDATE results.
Entities tagged with MERGE_ABSOLUTE and MERGE_DUPLICATE results are ignored.
The calling process must check the return value and call qof_book_merge_abort(mergeData) if non-zero.
mergeData | the merge context, QofBookMergeData* | |
tag | the result to attempt to set, QofBookMergeResult |
Definition at line 1186 of file qofbookmerge.c.
01186 { 01187 g_list_free (check); 01188 return 1; 01189 } 01190 } 01191 g_list_free (check); 01192 qof_book_merge_commit_foreach (qof_book_merge_commit_rule_loop, 01193 MERGE_NEW, mergeData); 01194 qof_book_merge_commit_foreach (qof_book_merge_commit_rule_loop, 01195 MERGE_UPDATE, mergeData); 01196 /* Placeholder for QofObject merge_helper_cb - all objects 01197 and all parameters set */ 01198 while (mergeData->mergeList != NULL) 01199 { 01200 currentRule = mergeData->mergeList->data; 01201 g_slist_free (currentRule->mergeParam); 01202 g_slist_free (currentRule->linkedEntList); 01203 mergeData->mergeList = g_list_next (mergeData->mergeList); 01204 } 01205 g_list_free (mergeData->mergeList); 01206 g_slist_free (mergeData->mergeObjectParams); 01207 g_slist_free (mergeData->targetList); 01208 if (mergeData->orphan_list != NULL) 01209 g_slist_free (mergeData->orphan_list); 01210 g_hash_table_destroy (mergeData->target_table); 01211 g_free (mergeData); 01212 return 0; 01213 } 01214 01215 void