+2007-06-10 Ben Pfaff <blp@gnu.org>
+
+ * casereader-filter.c (casereader_filter_destroy): Make sure to
+ write all the remaining excluded cases to the casewriter, if any.
+
+ * caseinit.c (init_list_destroy): Rewrite.
+ (init_list_clear): Ditto.
+
+ * casegrouper.c (casegrouper_get_next_group): Always set *reader
+ to null when returning false.
+
2007-06-06 Ben Pfaff <blp@gnu.org>
Actually implement the new procedure code and adapt all of its
size_t key_cnt;
};
+/* Creates and returns a new case ordering for comparing cases
+ that represent dictionary DICT. The case ordering initially
+ contains no variables, so that all cases will compare as
+ equal. */
struct case_ordering *
case_ordering_create (const struct dictionary *dict)
{
return co;
}
+/* Creates and returns a clone of case ordering ORIG. */
struct case_ordering *
case_ordering_clone (const struct case_ordering *orig)
{
return co;
}
+/* Destroys case ordering CO. */
void
case_ordering_destroy (struct case_ordering *co)
{
}
}
+/* Returns the number of `union value's in the cases that case
+ ordering CO compares (taken from the dictionary used to
+ construct it). */
size_t
case_ordering_get_value_cnt (const struct case_ordering *co)
{
return co->value_cnt;
}
+/* Compares cases A and B given case ordering CO and returns a
+ strcmp()-type result. */
int
case_ordering_compare_cases (const struct ccase *a, const struct ccase *b,
const struct case_ordering *co)
return 0;
}
+/* Adds VAR to case ordering CO as an additional sort key in sort
+ direction DIR. Returns true if successful, false if VAR was
+ already part of the ordering for CO. */
bool
case_ordering_add_var (struct case_ordering *co,
const struct variable *var, enum sort_direction dir)
return true;
}
+/* Returns the number of variables used for ordering within
+ CO. */
size_t
case_ordering_get_var_cnt (const struct case_ordering *co)
{
return co->key_cnt;
}
+/* Returns sort variable IDX within CO. An IDX of 0 returns the
+ primary sort key (the one added first), an IDX of 1 returns
+ the secondary sort key, and so on. IDX must be less than the
+ number of sort variables. */
const struct variable *
case_ordering_get_var (const struct case_ordering *co, size_t idx)
{
return co->keys[idx].var;
}
+/* Returns the sort direction for sort variable IDX within CO. */
enum sort_direction
case_ordering_get_direction (const struct case_ordering *co, size_t idx)
{
return co->keys[idx].dir;
}
+/* Stores an array listing all of the variables used for sorting
+ within CO into *VARS and the number of variables into
+ *VAR_CNT. The caller is responsible for freeing *VARS when it
+ is no longer needed. */
void
case_ordering_get_vars (const struct case_ordering *co,
const struct variable ***vars, size_t *var_cnt)
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
+/* Sort order for comparing cases. */
+
#ifndef DATA_CASE_ORDERING_H
#define DATA_CASE_ORDERING_H 1
SRT_DESCEND /* Z, Y, X, ..., C, B, A. */
};
+/* Creation and destruction. */
struct case_ordering *case_ordering_create (const struct dictionary *);
struct case_ordering *case_ordering_clone (const struct case_ordering *);
void case_ordering_destroy (struct case_ordering *);
-size_t case_ordering_get_value_cnt (const struct case_ordering *);
+/* Modification. */
+bool case_ordering_add_var (struct case_ordering *,
+ const struct variable *, enum sort_direction);
+
+/* Comparing cases. */
int case_ordering_compare_cases (const struct ccase *, const struct ccase *,
const struct case_ordering *);
-bool case_ordering_add_var (struct case_ordering *,
- const struct variable *, enum sort_direction);
+/* Inspection. */
+size_t case_ordering_get_value_cnt (const struct case_ordering *);
size_t case_ordering_get_var_cnt (const struct case_ordering *);
-const struct variable *case_ordering_get_var (const struct case_ordering *, size_t);
+const struct variable *case_ordering_get_var (const struct case_ordering *,
+ size_t);
enum sort_direction case_ordering_get_direction (const struct case_ordering *,
size_t);
void case_ordering_get_vars (const struct case_ordering *,
#include "xalloc.h"
+/* A casegrouper. */
struct casegrouper
{
- struct casereader *reader;
- struct taint *taint;
+ struct casereader *reader; /* Source of input cases. */
+ struct taint *taint; /* Error status for casegrouper. */
+ /* Functions for grouping cases. */
bool (*same_group) (const struct ccase *, const struct ccase *, void *aux);
void (*destroy) (void *aux);
void *aux;
};
+/* Creates and returns a new casegrouper that takes its input
+ from READER. SAME_GROUP is used to decide which cases are in
+ a group: it returns true if the pair of cases provided are in
+ the same group, false otherwise. DESTROY will be called when
+ the casegrouper is destroyed and should free any storage
+ needed by SAME_GROUP.
+
+ SAME_GROUP may be a null pointer. If so, READER's entire
+ contents is considered to be a single group. */
struct casegrouper *
casegrouper_create_func (struct casereader *reader,
bool (*same_group) (const struct ccase *,
return grouper;
}
-/* FIXME: we really shouldn't need a temporary casewriter for the
- common case where we read an entire group's data before going
- on to the next. */
+/* Obtains the next group of cases from GROUPER. Returns true if
+ successful, false if no groups remain. If successful, *READER
+ is set to the casereader for the new group; otherwise, it is
+ set to NULL. */
bool
casegrouper_get_next_group (struct casegrouper *grouper,
struct casereader **reader)
{
+ /* FIXME: we really shouldn't need a temporary casewriter for
+ the common case where we read an entire group's data before
+ going on to the next. */
if (grouper->same_group != NULL)
{
struct casewriter *writer;
return true;
}
else
- return false;
+ {
+ *reader = NULL;
+ return false;
+ }
}
}
+/* Destroys GROUPER. Returns false if GROUPER's input casereader
+ or any state derived from it had become tainted, which means
+ that an I/O error or other serious error occurred in
+ processing data derived from GROUPER; otherwise, return true. */
bool
casegrouper_destroy (struct casegrouper *grouper)
{
else
return true;
}
+\f
+/* Casegrouper based on equal values of variables from case to
+ case. */
+/* Casegrouper based on equal variables. */
struct casegrouper_vars
{
- const struct variable **vars;
- size_t var_cnt;
+ const struct variable **vars; /* Variables to compare. */
+ size_t var_cnt; /* Number of variables. */
};
-static bool
-casegrouper_vars_same_group (const struct ccase *a, const struct ccase *b,
- void *cv_)
-{
- struct casegrouper_vars *cv = cv_;
- return case_compare (a, b, cv->vars, cv->var_cnt) == 0;
-}
-
-static void
-casegrouper_vars_destroy (void *cv_)
-{
- struct casegrouper_vars *cv = cv_;
- free (cv->vars);
- free (cv);
-}
+static bool casegrouper_vars_same_group (const struct ccase *,
+ const struct ccase *,
+ void *);
+static void casegrouper_vars_destroy (void *);
+/* Creates and returns a casegrouper that reads data from READER
+ and breaks it into contiguous groups of cases that have equal
+ values for the VAR_CNT variables in VARS. If VAR_CNT is 0,
+ then all the cases will be put in a single group. */
struct casegrouper *
casegrouper_create_vars (struct casereader *reader,
const struct variable *const *vars,
return casegrouper_create_func (reader, NULL, NULL, NULL);
}
+/* Creates and returns a casegrouper that reads data from READER
+ and breaks it into contiguous groups of cases that have equal
+ values for the SPLIT FILE variables in DICT. If DICT has no
+ SPLIT FILE variables, then all the cases will be put into a
+ single group. */
struct casegrouper *
casegrouper_create_splits (struct casereader *reader,
const struct dictionary *dict)
dict_get_split_cnt (dict));
}
+/* Creates and returns a casegrouper that reads data from READER
+ and breaks it into contiguous groups of cases that have equal
+ values for the variables used for sorting in CO. If CO is
+ empty (contains no sort keys), then all the cases will be put
+ into a single group. */
struct casegrouper *
casegrouper_create_case_ordering (struct casereader *reader,
const struct case_ordering *co)
return grouper;
}
+
+/* "same_group" function for an equal-variables casegrouper. */
+static bool
+casegrouper_vars_same_group (const struct ccase *a, const struct ccase *b,
+ void *cv_)
+{
+ struct casegrouper_vars *cv = cv_;
+ return case_compare (a, b, cv->vars, cv->var_cnt) == 0;
+}
+
+/* "destroy" for an equal-variables casegrouper. */
+static void
+casegrouper_vars_destroy (void *cv_)
+{
+ struct casegrouper_vars *cv = cv_;
+ free (cv->vars);
+ free (cv);
+}
+
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
+/* Casegrouper.
+
+ Breaks up the cases from a casereader into sets of contiguous
+ cases based on some criteria, e.g. sets of cases that all have
+ the same values for some subset of variables. Each set of
+ cases is made available to the client as a casereader. */
+
#ifndef DATA_CASEGROUPER_H
#define DATA_CASEGROUPER_H 1
#include <libpspp/compiler.h>
#include "xalloc.h"
+\f
+/* Initializer list: a set of values to write to locations within
+ a case. */
+/* Binds a value with a place to put it. */
struct init_value
{
union value value;
size_t case_index;
};
+/* A set of values to initialize in a case. */
struct init_list
{
struct init_value *values;
size_t cnt;
};
+/* A bitmap of the "left" status of variables. */
enum leave_class
{
- LEAVE_REINIT = 0x001,
- LEAVE_LEFT = 0x002
+ LEAVE_REINIT = 0x001, /* Reinitalize for every case. */
+ LEAVE_LEFT = 0x002 /* Keep the value from one case to the next. */
};
+/* Initializes LIST as an empty initializer list. */
static void
init_list_create (struct init_list *list)
{
list->cnt = 0;
}
+/* Frees the storage associated with LIST. */
static void
-init_list_clear (struct init_list *list)
+init_list_destroy (struct init_list *list)
{
free (list->values);
- init_list_create (list);
}
+/* Clears LIST, making it an empty list. */
static void
-init_list_destroy (struct init_list *list)
+init_list_clear (struct init_list *list)
{
- init_list_clear (list);
+ init_list_destroy (list);
+ init_list_create (list);
}
+/* Compares `struct init_value's A and B by case_index and
+ returns a strcmp()-type result. */
static int
compare_init_values (const void *a_, const void *b_, const void *aux UNUSED)
{
return a->case_index < b->case_index ? -1 : a->case_index > b->case_index;
}
+/* Returns true if LIST includes CASE_INDEX, false otherwise. */
static bool
init_list_includes (const struct init_list *list, size_t case_index)
{
&value, compare_init_values, NULL) != NULL;
}
+/* Marks LIST to initialize the `union value's for the variables
+ in dictionary D that both (1) fall in the leave class or
+ classes designated by INCLUDE and (2) are not in EXCLUDE. */
static void
init_list_mark (struct init_list *list, const struct init_list *exclude,
enum leave_class include, const struct dictionary *d)
/* Drop duplicates. */
list->cnt = sort_unique (list->values, list->cnt, sizeof *list->values,
compare_init_values, NULL);
-
}
+/* Initializes data in case C to the values in the initializer
+ LIST. */
static void
init_list_init (const struct init_list *list, struct ccase *c)
{
}
}
+/* Updates the values in the initializer LIST from the data in
+ case C. */
static void
init_list_update (const struct init_list *list, const struct ccase *c)
{
value->value = *case_data_idx (c, value->case_index);
}
}
-
+\f
+/* A case initializer. */
struct caseinit
{
+ /* Values that do not need to be initialized by the
+ procedure, because they are initialized by the data
+ source. */
struct init_list preinited_values;
+
+ /* Values that need to be initialized to SYSMIS or spaces in
+ each case. */
struct init_list reinit_values;
+
+ /* Values that need to be initialized to 0 or spaces in the
+ first case and thereafter retain their values from case to
+ case. */
struct init_list left_values;
};
+/* Creates and returns a new case initializer. */
struct caseinit *
caseinit_create (void)
{
return ci;
}
+/* Clears the contents of case initializer CI. */
void
caseinit_clear (struct caseinit *ci)
{
init_list_clear (&ci->left_values);
}
+/* Destroys case initializer CI. */
void
caseinit_destroy (struct caseinit *ci)
{
}
}
+/* Marks the variables from dictionary D in CI as being
+ initialized by the data source, so that the case initializer
+ need not initialize them itself. */
void
caseinit_mark_as_preinited (struct caseinit *ci, const struct dictionary *d)
{
init_list_mark (&ci->preinited_values, NULL, LEAVE_REINIT | LEAVE_LEFT, d);
}
+/* Marks in CI the variables from dictionary D, except for any
+ variables that were already marked with
+ caseinit_mark_as_preinited, as needing initialization
+ according to their leave status. */
void
caseinit_mark_for_init (struct caseinit *ci, const struct dictionary *d)
{
init_list_mark (&ci->left_values, &ci->preinited_values, LEAVE_LEFT, d);
}
+/* Initializes variables in C as described by CI. */
void
-caseinit_init_reinit_vars (const struct caseinit *ci, struct ccase *c)
+caseinit_init_vars (const struct caseinit *ci, struct ccase *c)
{
init_list_init (&ci->reinit_values, c);
-}
-
-void caseinit_init_left_vars (const struct caseinit *ci, struct ccase *c)
-{
init_list_init (&ci->left_values, c);
}
+/* Updates the left vars in CI from the data in C, so that the
+ next call to caseinit_init_vars will store those values in the
+ next case. */
void
caseinit_update_left_vars (struct caseinit *ci, const struct ccase *c)
{
save the values of "left" variables to copy into the next case
read from the active file.
- The caseinit code helps with this. */
+ The caseinit data structure provides a little help for
+ tracking what data to initialize or to copy from case to
+ case. */
#ifndef DATA_CASEINIT_H
#define DATA_CASEINIT_H 1
struct dictionary;
struct ccase;
+/* Creation and destruction. */
struct caseinit *caseinit_create (void);
void caseinit_clear (struct caseinit *);
void caseinit_destroy (struct caseinit *);
+/* Track data to be initialized. */
void caseinit_mark_as_preinited (struct caseinit *, const struct dictionary *);
void caseinit_mark_for_init (struct caseinit *, const struct dictionary *);
-void caseinit_init_reinit_vars (const struct caseinit *, struct ccase *);
-void caseinit_init_left_vars (const struct caseinit *, struct ccase *);
+/* Initialize data and copy data from case to case. */
+void caseinit_init_vars (const struct caseinit *, struct ccase *);
void caseinit_update_left_vars (struct caseinit *, const struct ccase *);
#endif /* data/caseinit.h */
#include "gettext.h"
#define _(msgid) gettext (msgid)
+/* A casereader that filters data coming from another
+ casereader. */
struct casereader_filter
{
- struct casereader *subreader;
+ struct casereader *subreader; /* The reader to filter. */
bool (*include) (const struct ccase *, void *aux);
bool (*destroy) (void *aux);
void *aux;
- struct casewriter *exclude;
+ struct casewriter *exclude; /* Writer that gets filtered cases, or NULL. */
};
static struct casereader_class casereader_filter_class;
+/* Creates and returns a casereader whose content is a filtered
+ version of the data in SUBREADER. Only the cases for which
+ INCLUDE returns true will appear in the returned casereader,
+ in the original order.
+
+ If EXCLUDE is non-null, then cases for which INCLUDE returns
+ false are written to EXCLUDE. These cases will not
+ necessarily be fully written to EXCLUDE until the filtering casereader's
+ cases have been fully read or, if that never occurs, until the
+ filtering casereader is destroyed.
+
+ When the filtering casereader is destroyed, DESTROY will be
+ called to allow any state maintained by INCLUDE to be freed.
+
+ After this function is called, SUBREADER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the filtering casereader is destroyed. */
struct casereader *
casereader_create_filter_func (struct casereader *subreader,
bool (*include) (const struct ccase *,
return reader;
}
+/* Internal read function for filtering casereader. */
static bool
casereader_filter_read (struct casereader *reader UNUSED, void *filter_,
struct ccase *c)
}
}
+/* Internal destruction function for filtering casereader. */
static void
casereader_filter_destroy (struct casereader *reader, void *filter_)
{
struct casereader_filter *filter = filter_;
+
+ /* Make sure we've written everything to the excluded cases
+ casewriter, if there is one. */
+ if (filter->exclude != NULL)
+ {
+ struct ccase c;
+ while (casereader_read (filter->subreader, &c))
+ if (filter->include (&c, filter->aux))
+ case_destroy (&c);
+ else
+ casewriter_write (filter->exclude, &c);
+ }
+
casereader_destroy (filter->subreader);
if (filter->destroy != NULL && !filter->destroy (filter->aux))
casereader_force_error (reader);
free (filter);
}
+/* Filtering casereader class. */
static struct casereader_class casereader_filter_class =
{
casereader_filter_read,
NULL,
};
+\f
+/* Casereader for filtering valid weights. */
+
+/* Weight-filtering data. */
struct casereader_filter_weight
{
- const struct variable *weight_var;
- bool *warn_on_invalid;
- bool local_warn_on_invalid;
+ const struct variable *weight_var; /* Weight variable. */
+ bool *warn_on_invalid; /* Have we already issued an error? */
+ bool local_warn_on_invalid; /* warn_on_invalid might point here. */
};
-static bool
-casereader_filter_weight_include (const struct ccase *c, void *cfw_)
-{
- struct casereader_filter_weight *cfw = cfw_;
- double value = case_num (c, cfw->weight_var);
- if (value >= 0.0 && !var_is_num_missing (cfw->weight_var, value, MV_ANY))
- return true;
- else
- {
- if (*cfw->warn_on_invalid)
- {
- msg (SW, _("At least one case in the data read had a weight value "
- "that was user-missing, system-missing, zero, or "
- "negative. These case(s) were ignored."));
- *cfw->warn_on_invalid = false;
- }
- return false;
- }
-}
+static bool casereader_filter_weight_include (const struct ccase *, void *);
+static bool casereader_filter_weight_destroy (void *);
-static bool
-casereader_filter_weight_destroy (void *cfw_)
-{
- struct casereader_filter_weight *cfw = cfw_;
- free (cfw);
- return true;
-}
+/* Creates and returns a casereader that filters cases from
+ READER by valid weights, that is, any cases with user- or
+ system-missing, zero, or negative weights are dropped. The
+ weight variable's information is taken from DICT. If DICT
+ does not have a weight variable, then no cases are filtered
+ out.
+
+ When a case with an invalid weight is encountered,
+ *WARN_ON_INVALID is checked. If it is true, then an error
+ message is issued and *WARN_ON_INVALID is set false. If
+ WARN_ON_INVALID is a null pointer, then an internal bool that
+ is initially true is used instead of a caller-supplied bool.
+ If EXCLUDE is non-null, then dropped cases are written to
+ EXCLUDE. These cases will not necessarily be fully written to
+ EXCLUDE until the filtering casereader's cases have been fully
+ read or, if that never occurs, until the filtering casereader
+ is destroyed.
+
+ After this function is called, READER must not ever again be
+ referenced directly. It will be destroyed automatically when
+ the filtering casereader is destroyed. */
struct casereader *
casereader_create_filter_weight (struct casereader *reader,
const struct dictionary *dict,
reader = casereader_rename (reader);
return reader;
}
-\f
-struct casereader_filter_missing
- {
- struct variable **vars;
- size_t var_cnt;
- enum mv_class class;
- };
+/* Internal "include" function for weight-filtering
+ casereader. */
static bool
-casereader_filter_missing_include (const struct ccase *c, void *cfm_)
+casereader_filter_weight_include (const struct ccase *c, void *cfw_)
{
- const struct casereader_filter_missing *cfm = cfm_;
- size_t i;
-
- for (i = 0; i < cfm->var_cnt; i++)
+ struct casereader_filter_weight *cfw = cfw_;
+ double value = case_num (c, cfw->weight_var);
+ if (value >= 0.0 && !var_is_num_missing (cfw->weight_var, value, MV_ANY))
+ return true;
+ else
{
- struct variable *var = cfm->vars[i];
- const union value *value = case_data (c, var);
- if (var_is_value_missing (var, value, cfm->class))
- return false;
+ if (*cfw->warn_on_invalid)
+ {
+ msg (SW, _("At least one case in the data read had a weight value "
+ "that was user-missing, system-missing, zero, or "
+ "negative. These case(s) were ignored."));
+ *cfw->warn_on_invalid = false;
+ }
+ return false;
}
- return true;
}
+/* Internal "destroy" function for weight-filtering
+ casereader. */
static bool
-casereader_filter_missing_destroy (void *cfm_)
+casereader_filter_weight_destroy (void *cfw_)
{
- struct casereader_filter_missing *cfm = cfm_;
- free (cfm->vars);
- free (cfm);
+ struct casereader_filter_weight *cfw = cfw_;
+ free (cfw);
return true;
}
+\f
+/* Casereader for filtering missing values. */
+
+/* Missing-value filtering data. */
+struct casereader_filter_missing
+ {
+ struct variable **vars; /* Variables whose values to filter. */
+ size_t var_cnt; /* Number of variables. */
+ enum mv_class class; /* Types of missing values to filter. */
+ };
+
+static bool casereader_filter_missing_include (const struct ccase *, void *);
+static bool casereader_filter_missing_destroy (void *);
+
+/* Creates and returns a casereader that filters out cases from
+ READER that have a missing value in the given CLASS for any of
+ the VAR_CNT variables in VARS. Only cases that have
+ non-missing values for all of these variables are passed
+ through.
+ Ownership of VARS is retained by the caller.
+
+ If EXCLUDE is non-null, then dropped cases are written to
+ EXCLUDE. These cases will not necessarily be fully written to
+ EXCLUDE until the filtering casereader's cases have been fully
+ read or, if that never occurs, until the filtering casereader
+ is destroyed.
+
+ After this function is called, READER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the filtering casereader is destroyed. */
struct casereader *
casereader_create_filter_missing (struct casereader *reader,
const struct variable **vars, size_t var_cnt,
else
return casereader_rename (reader);
}
-\f
-\f
+
+/* Internal "include" function for missing value-filtering
+ casereader. */
static bool
-casereader_counter_include (const struct ccase *c UNUSED, void *counter_)
+casereader_filter_missing_include (const struct ccase *c, void *cfm_)
{
- casenumber *counter = counter_;
- ++*counter;
+ const struct casereader_filter_missing *cfm = cfm_;
+ size_t i;
+
+ for (i = 0; i < cfm->var_cnt; i++)
+ {
+ struct variable *var = cfm->vars[i];
+ const union value *value = case_data (c, var);
+ if (var_is_value_missing (var, value, cfm->class))
+ return false;
+ }
+ return true;
+}
+
+/* Internal "destroy" function for missing value-filtering
+ casereader. */
+static bool
+casereader_filter_missing_destroy (void *cfm_)
+{
+ struct casereader_filter_missing *cfm = cfm_;
+ free (cfm->vars);
+ free (cfm);
return true;
}
+\f
+/* Case-counting casereader. */
+
+static bool casereader_counter_include (const struct ccase *, void *);
+/* Creates and returns a new casereader that counts the number of
+ cases that have been read from it. *COUNTER is initially set
+ to INITIAL_VALUE, then incremented by 1 each time a case is read.
+
+ Counting casereaders must be used very cautiously: if a
+ counting casereader is cloned or if the casereader_peek
+ function is used on it, then the counter's value can be higher
+ than expected because of the buffering that goes on behind the
+ scenes.
+
+ The counter is only incremented as cases are actually read
+ from the casereader. In particular, if the casereader is
+ destroyed before all cases have been read from the casereader,
+ cases never read will not be included in the count.
+
+ After this function is called, READER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the filtering casereader is destroyed. */
struct casereader *
casereader_create_counter (struct casereader *reader, casenumber *counter,
casenumber initial_value)
return casereader_create_filter_func (reader, casereader_counter_include,
NULL, counter, NULL);
}
+
+/* Internal "include" function for counting casereader. */
+static bool
+casereader_counter_include (const struct ccase *c UNUSED, void *counter_)
+{
+ casenumber *counter = counter_;
+ ++*counter;
+ return true;
+}
#include "xalloc.h"
+/* Casereader that applies a user-supplied function to translate
+ each case into another in an arbitrary fashion. */
+
+/* A translating casereader. */
struct casereader_translator
{
- struct casereader *subreader;
+ struct casereader *subreader; /* Source of input cases. */
void (*translate) (const struct ccase *input, struct ccase *output,
void *aux);
static struct casereader_class casereader_translator_class;
+/* Creates and returns a new casereader whose cases are produced
+ by reading from SUBREADER and passing through TRANSLATE, which
+ must create case OUTPUT, with OUTPUT_VALUE_CNT values, and
+ populate it based on INPUT and auxiliary data AUX. TRANSLATE
+ must also destroy INPUT.
+
+ When the translating casereader is destroyed, DESTROY will be
+ called to allow any state maintained by TRANSLATE to be freed.
+
+ After this function is called, SUBREADER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the translating casereader is destroyed. */
struct casereader *
casereader_create_translator (struct casereader *subreader,
size_t output_value_cnt,
return reader;
}
+/* Internal read function for translating casereader. */
static bool
casereader_translator_read (struct casereader *reader UNUSED,
void *ct_, struct ccase *c)
return false;
}
+/* Internal destroy function for translating casereader. */
static void
casereader_translator_destroy (struct casereader *reader UNUSED, void *ct_)
{
free (ct);
}
+/* Casereader class for translating casereader. */
static struct casereader_class casereader_translator_class =
{
casereader_translator_read,
return new;
}
-/* Returns true if a I/O error has occurred while processing a
- datasheet operation. */
+/* Returns true if datasheet DS is tainted.
+ A datasheet is tainted by an I/O error or by taint
+ propagation to the datasheet. */
bool
datasheet_error (const struct datasheet *ds)
{
return taint_is_tainted (ds->taint);
}
+/* Marks datasheet DS tainted. */
void
datasheet_force_error (struct datasheet *ds)
{
taint_set_taint (ds->taint);
}
+/* Returns datasheet DS's taint object. */
const struct taint *
datasheet_get_taint (const struct datasheet *ds)
{
return reader;
}
+/* "read" function for the datasheet random casereader. */
static bool
datasheet_reader_read (struct casereader *reader UNUSED, void *ds_,
casenumber case_idx, struct ccase *c)
}
}
+/* "destroy" function for the datasheet random casereader. */
static void
datasheet_reader_destroy (struct casereader *reader UNUSED, void *ds_)
{
datasheet_destroy (ds);
}
+/* "advance" function for the datasheet random casereader. */
static void
datasheet_reader_advance (struct casereader *reader UNUSED, void *ds_,
casenumber case_cnt)
datasheet_delete_rows (ds, 0, case_cnt);
}
+/* Random casereader class for a datasheet. */
static const struct casereader_random_class datasheet_reader_class =
{
datasheet_reader_read,
/* Procedure data. */
enum
{
- PROC_COMMITTED,
- PROC_OPEN,
- PROC_CLOSED
+ PROC_COMMITTED, /* No procedure in progress. */
+ PROC_OPEN, /* proc_open called, casereader still open. */
+ PROC_CLOSED /* casereader from proc_open destroyed,
+ but proc_commit not yet called. */
}
proc_state;
size_t cases_written; /* Cases output so far. */
&proc_casereader_class, ds);
}
+/* Returns true if a procedure is in progress, that is, if
+ proc_open has been called but proc_commit has not. */
bool
proc_is_open (const struct dataset *ds)
{
return ds->proc_state != PROC_COMMITTED;
}
-/* Reads the next case from dataset DS, which must have been
- opened for reading with proc_open.
- Returns true if successful, in which case a pointer to the
- case is stored in *C.
- Return false at end of file or if a read error occurs. In
- this case a null pointer is stored in *C. */
+/* "read" function for procedure casereader. */
static bool
proc_casereader_read (struct casereader *reader UNUSED, void *ds_,
struct ccase *c)
if (!casereader_read (ds->source, c))
return false;
case_resize (c, dict_get_next_value_idx (ds->dict));
- caseinit_init_reinit_vars (ds->caseinit, c);
- caseinit_init_left_vars (ds->caseinit, c);
+ caseinit_init_vars (ds->caseinit, c);
/* Execute permanent transformations. */
case_nr = ds->cases_written + 1;
}
}
-/* Closes dataset DS for reading.
- Returns true if successful, false if an I/O error occurred
- while reading or closing the data set.
- If DS has not been opened, returns true without doing
- anything else. */
+/* "destroy" function for procedure casereader. */
static void
proc_casereader_destroy (struct casereader *reader, void *ds_)
{
return proc_cancel_all_transformations (ds) && ds->ok;
}
+/* Casereader class for procedure execution. */
static struct casereader_class proc_casereader_class =
{
proc_casereader_read,