diff options
Diffstat (limited to 'src/bin/pg_rewind/filemap.h')
| -rw-r--r-- | src/bin/pg_rewind/filemap.h | 76 |
1 files changed, 49 insertions, 27 deletions
diff --git a/src/bin/pg_rewind/filemap.h b/src/bin/pg_rewind/filemap.h index 0cb7425170c..3d423558734 100644 --- a/src/bin/pg_rewind/filemap.h +++ b/src/bin/pg_rewind/filemap.h @@ -14,17 +14,22 @@ /* * For every file found in the local or remote system, we have a file entry - * which says what we are going to do with the file. For relation files, - * there is also a page map, marking pages in the file that were changed - * locally. - * - * The enum values are sorted in the order we want actions to be processed. + * that contains information about the file on both systems. For relation + * files, there is also a page map that marks pages in the file that were + * changed in the target after the last common checkpoint. Each entry also + * contains an 'action' field, which says what we are going to do with the + * file. */ + +/* these enum values are sorted in the order we want actions to be processed */ typedef enum { + FILE_ACTION_UNDECIDED = 0, /* not decided yet */ + FILE_ACTION_CREATE, /* create local directory or symbolic link */ FILE_ACTION_COPY, /* copy whole file, overwriting if exists */ - FILE_ACTION_COPY_TAIL, /* copy tail from 'oldsize' to 'newsize' */ + FILE_ACTION_COPY_TAIL, /* copy tail from 'source_size' to + * 'target_size' */ FILE_ACTION_NONE, /* no action (we might still copy modified * blocks based on the parsed WAL) */ FILE_ACTION_TRUNCATE, /* truncate local file to 'newsize' bytes */ @@ -33,6 +38,8 @@ typedef enum typedef enum { + FILE_TYPE_UNDEFINED = 0, + FILE_TYPE_REGULAR, FILE_TYPE_DIRECTORY, FILE_TYPE_SYMLINK @@ -41,19 +48,34 @@ typedef enum typedef struct file_entry_t { char *path; - file_type_t type; + bool isrelfile; /* is it a relation data file? */ - file_action_t action; + /* + * Status of the file in the target. + */ + bool target_exists; + file_type_t target_type; + size_t target_size; /* for a regular file */ + char *target_link_target; /* for a symlink */ - /* for a regular file */ - size_t oldsize; - size_t newsize; - bool isrelfile; /* is it a relation data file? */ + /* + * Pages that were modified in the target and need to be replaced from the + * source. + */ + datapagemap_t target_pages_to_overwrite; - datapagemap_t pagemap; + /* + * Status of the file in the source. + */ + bool source_exists; + file_type_t source_type; + size_t source_size; + char *source_link_target; /* for a symlink */ - /* for a symlink */ - char *link_target; + /* + * What will we do to the file? + */ + file_action_t action; struct file_entry_t *next; } file_entry_t; @@ -71,19 +93,18 @@ typedef struct filemap_t /* * After processing all the remote files, the entries in the linked list * are moved to this array. After processing local files, too, all the - * local entries are added to the array by filemap_finalize, and sorted in - * the final order. After filemap_finalize, all the entries are in the - * array, and the linked list is empty. + * local entries are added to the array by decide_file_actions(), and + * sorted in the final order. After decide_file_actions(), all the entries + * are in the array, and the linked list is empty. */ file_entry_t **array; int narray; /* current length of array */ /* - * Summary information. total_size is the total size of the source - * cluster, and fetch_size is the number of bytes that needs to be copied. + * Summary information. */ - uint64 total_size; - uint64 fetch_size; + uint64 total_size; /* total size of the source cluster */ + uint64 fetch_size; /* number of bytes that needs to be copied */ } filemap_t; extern filemap_t *filemap; @@ -94,11 +115,12 @@ extern void print_filemap(void); /* Functions for populating the filemap */ extern void process_source_file(const char *path, file_type_t type, - size_t newsize, const char *link_target); + size_t size, const char *link_target); extern void process_target_file(const char *path, file_type_t type, - size_t newsize, const char *link_target); -extern void process_block_change(ForkNumber forknum, RelFileNode rnode, - BlockNumber blkno); -extern void filemap_finalize(void); + size_t size, const char *link_target); +extern void process_target_wal_block_change(ForkNumber forknum, + RelFileNode rnode, + BlockNumber blkno); +extern void decide_file_actions(void); #endif /* FILEMAP_H */ |