diff options
author | Thomas White <taw@physics.org> | 2020-09-04 12:15:49 +0200 |
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committer | Thomas White <taw@physics.org> | 2020-09-04 12:15:49 +0200 |
commit | cf295e657e59acb6bf0a2e226572b35927daa258 (patch) | |
tree | c9590da7e0f4769f14f256daaafdad8b200b0daf /libcrystfel/src | |
parent | f5b3c4db36fabb2c4482bb512fb9a8f1adde6411 (diff) |
New API for random access to stream
Diffstat (limited to 'libcrystfel/src')
-rw-r--r-- | libcrystfel/src/stream.c | 192 | ||||
-rw-r--r-- | libcrystfel/src/stream.h | 8 |
2 files changed, 149 insertions, 51 deletions
diff --git a/libcrystfel/src/stream.c b/libcrystfel/src/stream.c index e4c3b333..76f1344b 100644 --- a/libcrystfel/src/stream.c +++ b/libcrystfel/src/stream.c @@ -1419,78 +1419,172 @@ int stream_rewind(Stream *st) } -int stream_select_chunk(Stream *st, int chunk_id) +struct _streamindex { - if ( st->chunk_offsets == NULL ) return 1; - if ( chunk_id >= st->n_chunks ) return 1; - if ( fseek(st->fh, st->chunk_offsets[chunk_id], SEEK_SET) != 0 ) { - return 1; + char **keys; + long int *ptrs; + int n_keys; + int max_keys; +}; + + +void stream_index_free(StreamIndex *index) +{ + if ( index == NULL ) return; + free(index->keys); + free(index->ptrs); + free(index); +} + + +static char *make_key(const char *filename, + const char *ev) +{ + char *key; + + key = malloc(strlen(filename)+strlen(ev)+2); + if ( key == NULL ) return NULL; + + strcpy(key, filename); + strcat(key, " "); + strcat(key, ev); + + return key; +} + + +int stream_select_chunk(Stream *st, + StreamIndex *index, + const char *filename, + const char *ev) +{ + int i; + char *key; + + if ( index == NULL ) return 1; + + key = make_key(filename, ev); + for ( i=0; i<index->n_keys; i++ ) { + if ( strcmp(index->keys[i], key) == 0 ) { + if ( st != NULL ) { + fseek(st->fh, index->ptrs[i], SEEK_SET); + st->in_chunk = 0; + } + return 0; + } } - st->in_chunk = 1; - return 0; + return 1; } -int stream_scan_chunks(Stream *st) +static void add_index_record(StreamIndex *index, + long int ptr, + const char *filename, + const char *ev) { - long start_pos; - long int max_chunks = 0; - int done = 0; + char *key; + + if ( index->n_keys == index->max_keys ) { + + int new_max_keys = index->max_keys + 256; + char **new_keys; + long int *new_ptrs; + + new_keys = realloc(index->keys, + new_max_keys*sizeof(char *)); + if ( new_keys == NULL ) return; + + new_ptrs = realloc(index->ptrs, + new_max_keys*sizeof(long int)); + if ( new_ptrs == NULL ) return; + + index->keys = new_keys; + index->ptrs = new_ptrs; + index->max_keys = new_max_keys; - if ( st->chunk_offsets != NULL ) { - ERROR("Stream has already been scanned\n"); - return 0; } - start_pos = ftell(st->fh); + key = make_key(filename, ev); + if ( key == NULL ) return; - /* Reset to start of stream. - * Also, this serves as a cursory check that the stream is - * actually something which can be rewound. */ - if ( fseek(st->fh, 0, SEEK_SET) != 0 ) { - return 0; + index->keys[index->n_keys] = key; + index->ptrs[index->n_keys] = ptr; + index->n_keys++; +} + + +StreamIndex *stream_make_index(const char *filename) +{ + FILE *fh; + StreamIndex *index; + long int last_start_pos = 0; + char *last_filename = NULL; + char *last_ev = NULL; + int done = 0; + + fh = fopen(filename, "r"); + if ( fh == NULL ) return NULL; + + index = malloc(sizeof(StreamIndex)); + if ( index == NULL ) { + fclose(fh); + return NULL; } - do { + index->keys = NULL; + index->ptrs = NULL; + index->n_keys = 0; + index->max_keys = 0; - if ( find_start_of_chunk(st) ) { + STATUS("Indexing %s\n", filename); - if ( feof(st->fh) ) { - done = 1; - } else { - fseek(st->fh, start_pos, SEEK_SET); - free(st->chunk_offsets); - st->chunk_offsets = NULL; - return 0; - } - } + do { - if ( st->n_chunks == max_chunks ) { + char *rval; + char line[1024]; + long int pos; - long *new_offsets; + pos = ftell(fh); + rval = fgets(line, 1024, fh); + if ( rval == NULL ) { + done = 1; + break; + } + chomp(line); - max_chunks += 1024; - new_offsets = realloc(st->chunk_offsets, - max_chunks*sizeof(long)); - if ( new_offsets == NULL ) { - fseek(st->fh, start_pos, SEEK_SET); - free(st->chunk_offsets); - st->chunk_offsets = NULL; - return 0; - } + if ( strcmp(line, STREAM_CHUNK_START_MARKER) == 0 ) { + last_start_pos = pos; + last_filename = NULL; + last_ev = NULL; + } - st->chunk_offsets = new_offsets; + if ( strncmp(line, "Image filename: ", 16) == 0 ) { + last_filename = strdup(line+16); + } + if ( strncmp(line, "Event: ", 7) == 0 ) { + last_ev = strdup(line+7); } - if ( !done ) { - st->chunk_offsets[st->n_chunks++] = ftell(st->fh); + if ( strcmp(line, STREAM_CHUNK_END_MARKER) == 0 ) { + if ( (last_start_pos != 0) + && (last_filename != NULL) + && (last_ev != NULL) ) + { + add_index_record(index, + last_start_pos, + last_filename, + last_ev); + } + free(last_filename); + free(last_ev); + last_start_pos = 0; + last_filename = NULL; + last_ev = NULL; } } while ( !done ); - /* Reset to initial position */ - fseek(st->fh, start_pos, SEEK_SET); - - return st->n_chunks; + fclose(fh); + return index; } diff --git a/libcrystfel/src/stream.h b/libcrystfel/src/stream.h index 9f19e524..5eadf69b 100644 --- a/libcrystfel/src/stream.h +++ b/libcrystfel/src/stream.h @@ -109,8 +109,12 @@ extern int stream_get_fd(Stream *st); extern int stream_rewind(Stream *st); /* Random access */ -extern int stream_scan_chunks(Stream *st); -extern int stream_select_chunk(Stream *st, int chunk_number); +typedef struct _streamindex StreamIndex; +extern StreamIndex *stream_make_index(const char *filename); +extern int stream_select_chunk(Stream *st, StreamIndex *index, + const char *filename, + const char *ev); +extern void stream_index_free(StreamIndex *index); /* Read/write chunks */ extern struct image *stream_read_chunk(Stream *st, StreamFlags srf); |