src/interfaces/ecpg/preproc/descriptor.c - master - githubmirror/postgres

src/interfaces/ecpg/preproc/descriptor.c
367 строк9 KB
Tom Lane
Pre-beta mechanical code beautification, step 1: run pgindent.
13 май 2026, 17:34
13 май 2026, 17:34020794e
/*
 * functions needed for descriptor handling
 *
 * src/interfaces/ecpg/preproc/descriptor.c
 *
 * since descriptor might be either a string constant or a string var
 * we need to check for a constant if we expect a constant
 */

#include "postgres_fe.h"

#include "preproc_extern.h"

/*
 * assignment handling function (descriptor)
 */

static struct assignment *assignments;

void
push_assignment(const char *var, enum ECPGdtype value)
{
	struct assignment *new = (struct assignment *) mm_alloc(sizeof(struct assignment));

	new->next = assignments;
	new->variable = mm_strdup(var);
	new->value = value;
	assignments = new;
}

static void
drop_assignments(void)
{
	while (assignments)
	{
		struct assignment *old_head = assignments;

		assignments = old_head->next;
		free(old_head->variable);
		free(old_head);
	}
}

static void
ECPGnumeric_lvalue(char *name)
{
	const struct variable *v = find_variable(name);

	switch (v->type->type)
	{
		case ECPGt_short:
		case ECPGt_int:
		case ECPGt_long:
		case ECPGt_long_long:
		case ECPGt_unsigned_short:
		case ECPGt_unsigned_int:
		case ECPGt_unsigned_long:
		case ECPGt_unsigned_long_long:
		case ECPGt_const:
			fputs(name, base_yyout);
			break;
		default:
			mmerror(PARSE_ERROR, ET_ERROR, "variable \"%s\" must have a numeric type", name);
			break;
	}
}

/*
 * descriptor name lookup
 */

static struct descriptor *descriptors;

void
add_descriptor(const char *name, const char *connection)
{
	struct descriptor *new;

	if (name[0] != '"')
		return;

	new = (struct descriptor *) mm_alloc(sizeof(struct descriptor));

	new->next = descriptors;
	new->name = mm_strdup(name);
	if (connection)
		new->connection = mm_strdup(connection);
	else
		new->connection = NULL;
	descriptors = new;
}

void
drop_descriptor(const char *name, const char *connection)
{
	struct descriptor *i;
	struct descriptor **lastptr = &descriptors;

	if (name[0] != '"')
		return;

	for (i = descriptors; i; lastptr = &i->next, i = i->next)
	{
		if (strcmp(name, i->name) == 0)
		{
			if ((!connection && !i->connection)
				|| (connection && i->connection
					&& strcmp(connection, i->connection) == 0))
			{
				*lastptr = i->next;
				free(i->connection);
				free(i->name);
				free(i);
				return;
			}
		}
	}
	if (connection)
		mmerror(PARSE_ERROR, ET_WARNING, "descriptor %s bound to connection %s does not exist", name, connection);
	else
		mmerror(PARSE_ERROR, ET_WARNING, "descriptor %s bound to the default connection does not exist", name);
}

struct descriptor *
lookup_descriptor(const char *name, const char *connection)
{
	struct descriptor *i;

	if (name[0] != '"')
		return NULL;

	for (i = descriptors; i; i = i->next)
	{
		if (strcmp(name, i->name) == 0)
		{
			if ((!connection && !i->connection)
				|| (connection && i->connection
					&& strcmp(connection, i->connection) == 0))
				return i;
			if (connection && !i->connection)
			{
				/* overwrite descriptor's connection */
				i->connection = mm_strdup(connection);
				return i;
			}
		}
	}
	if (connection)
		mmerror(PARSE_ERROR, ET_WARNING, "descriptor %s bound to connection %s does not exist", name, connection);
	else
		mmerror(PARSE_ERROR, ET_WARNING, "descriptor %s bound to the default connection does not exist", name);
	return NULL;
}

void
output_get_descr_header(const char *desc_name)
{
	struct assignment *results;

	fprintf(base_yyout, "{ ECPGget_desc_header(__LINE__, %s, &(", desc_name);
	for (results = assignments; results != NULL; results = results->next)
	{
		if (results->value == ECPGd_count)
			ECPGnumeric_lvalue(results->variable);
		else
			mmerror(PARSE_ERROR, ET_WARNING, "descriptor header item \"%d\" does not exist", results->value);
	}

	drop_assignments();
	fprintf(base_yyout, "));\n");
	whenever_action(3);
}

void
output_get_descr(const char *desc_name, const char *index)
{
	struct assignment *results;

	fprintf(base_yyout, "{ ECPGget_desc(__LINE__, %s, %s,", desc_name, index);
	for (results = assignments; results != NULL; results = results->next)
	{
		const struct variable *v = find_variable(results->variable);
		char	   *str_zero = mm_strdup("0");

		switch (results->value)
		{
			case ECPGd_nullable:
				mmerror(PARSE_ERROR, ET_WARNING, "nullable is always 1");
				break;
			case ECPGd_key_member:
				mmerror(PARSE_ERROR, ET_WARNING, "key_member is always 0");
				break;
			default:
				break;
		}
		fprintf(base_yyout, "%s,", get_dtype(results->value));
		ECPGdump_a_type(base_yyout, v->name, v->type, v->brace_level,
						NULL, NULL, -1, NULL, NULL, str_zero, NULL, NULL);
		free(str_zero);
	}
	drop_assignments();
	fputs("ECPGd_EODT);\n", base_yyout);

	whenever_action(2 | 1);
}

void
output_set_descr_header(const char *desc_name)
{
	struct assignment *results;

	fprintf(base_yyout, "{ ECPGset_desc_header(__LINE__, %s, (int)(", desc_name);
	for (results = assignments; results != NULL; results = results->next)
	{
		if (results->value == ECPGd_count)
			ECPGnumeric_lvalue(results->variable);
		else
			mmerror(PARSE_ERROR, ET_WARNING, "descriptor header item \"%d\" does not exist", results->value);
	}

	drop_assignments();
	fprintf(base_yyout, "));\n");
	whenever_action(3);
}

static const char *
descriptor_item_name(enum ECPGdtype itemcode)
{
	switch (itemcode)
	{
		case ECPGd_cardinality:
			return "CARDINALITY";
		case ECPGd_count:
			return "COUNT";
		case ECPGd_data:
			return "DATA";
		case ECPGd_di_code:
			return "DATETIME_INTERVAL_CODE";
		case ECPGd_di_precision:
			return "DATETIME_INTERVAL_PRECISION";
		case ECPGd_indicator:
			return "INDICATOR";
		case ECPGd_key_member:
			return "KEY_MEMBER";
		case ECPGd_length:
			return "LENGTH";
		case ECPGd_name:
			return "NAME";
		case ECPGd_nullable:
			return "NULLABLE";
		case ECPGd_octet:
			return "OCTET_LENGTH";
		case ECPGd_precision:
			return "PRECISION";
		case ECPGd_ret_length:
			return "RETURNED_LENGTH";
		case ECPGd_ret_octet:
			return "RETURNED_OCTET_LENGTH";
		case ECPGd_scale:
			return "SCALE";
		case ECPGd_type:
			return "TYPE";
		default:
			return NULL;
	}
}

void
output_set_descr(const char *desc_name, const char *index)
{
	struct assignment *results;

	fprintf(base_yyout, "{ ECPGset_desc(__LINE__, %s, %s,", desc_name, index);
	for (results = assignments; results != NULL; results = results->next)
	{
		const struct variable *v = find_variable(results->variable);

		switch (results->value)
		{
			case ECPGd_cardinality:
			case ECPGd_di_code:
			case ECPGd_di_precision:
			case ECPGd_precision:
			case ECPGd_scale:
				mmfatal(PARSE_ERROR, "descriptor item \"%s\" is not implemented",
						descriptor_item_name(results->value));
				break;

			case ECPGd_key_member:
			case ECPGd_name:
			case ECPGd_nullable:
			case ECPGd_octet:
			case ECPGd_ret_length:
			case ECPGd_ret_octet:
				mmfatal(PARSE_ERROR, "descriptor item \"%s\" cannot be set",
						descriptor_item_name(results->value));
				break;

			case ECPGd_data:
			case ECPGd_indicator:
			case ECPGd_length:
			case ECPGd_type:
				{
					char	   *str_zero = mm_strdup("0");

					fprintf(base_yyout, "%s,", get_dtype(results->value));
					ECPGdump_a_type(base_yyout, v->name, v->type, v->brace_level,
									NULL, NULL, -1, NULL, NULL, str_zero, NULL, NULL);
					free(str_zero);
				}
				break;

			default:
				;
		}
	}
	drop_assignments();
	fputs("ECPGd_EODT);\n", base_yyout);

	whenever_action(2 | 1);
}

/*
 * I consider dynamic allocation overkill since at most two descriptor
 * variables are possible per statement. (input and output descriptor)
 * And descriptors are no normal variables, so they don't belong into
 * the variable list.
 */

#define MAX_DESCRIPTOR_NAMELEN 128
struct variable *
descriptor_variable(const char *name, int input)
{
	static char descriptor_names[2][MAX_DESCRIPTOR_NAMELEN];
	static struct ECPGtype descriptor_type = {ECPGt_descriptor, NULL, NULL, NULL, {NULL}, 0};
	static struct variable varspace[2] = {
		{descriptor_names[0], &descriptor_type, 0, NULL},
		{descriptor_names[1], &descriptor_type, 0, NULL}
	};

	strlcpy(descriptor_names[input], name, sizeof(descriptor_names[input]));
	return &varspace[input];
}

struct variable *
sqlda_variable(const char *name)
{
	/*
	 * Presently, sqlda variables are only needed for the duration of the
	 * current statement.  Rather than add infrastructure to manage them,
	 * let's just loc_alloc them.
	 */
	struct variable *p = (struct variable *) loc_alloc(sizeof(struct variable));

	p->name = loc_strdup(name);
	p->type = (struct ECPGtype *) loc_alloc(sizeof(struct ECPGtype));
	p->type->type = ECPGt_sqlda;
	p->type->type_name = NULL;
	p->type->size = NULL;
	p->type->struct_sizeof = NULL;
	p->type->u.element = NULL;
	p->type->counter = 0;
	p->brace_level = 0;
	p->next = NULL;

	return p;
}