From 2a969b7f4bdb223d3626dc14b684701942ccafb2 Mon Sep 17 00:00:00 2001 From: Karen Arutyunov Date: Thu, 21 Sep 2017 01:02:04 +0300 Subject: Make package to be source rather than stub --- libpq/pqexpbuffer.h | 182 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) create mode 100644 libpq/pqexpbuffer.h (limited to 'libpq/pqexpbuffer.h') diff --git a/libpq/pqexpbuffer.h b/libpq/pqexpbuffer.h new file mode 100644 index 0000000..ce87cd5 --- /dev/null +++ b/libpq/pqexpbuffer.h @@ -0,0 +1,182 @@ +/*------------------------------------------------------------------------- + * + * pqexpbuffer.h + * Declarations/definitions for "PQExpBuffer" functions. + * + * PQExpBuffer provides an indefinitely-extensible string data type. + * It can be used to buffer either ordinary C strings (null-terminated text) + * or arbitrary binary data. All storage is allocated with malloc(). + * + * This module is essentially the same as the backend's StringInfo data type, + * but it is intended for use in frontend libpq and client applications. + * Thus, it does not rely on palloc() nor elog(). + * + * It does rely on vsnprintf(); if configure finds that libc doesn't provide + * a usable vsnprintf(), then a copy of our own implementation of it will + * be linked into libpq. + * + * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/interfaces/libpq/pqexpbuffer.h + * + *------------------------------------------------------------------------- + */ +#ifndef PQEXPBUFFER_H +#define PQEXPBUFFER_H + +/*------------------------- + * PQExpBufferData holds information about an extensible string. + * data is the current buffer for the string (allocated with malloc). + * len is the current string length. There is guaranteed to be + * a terminating '\0' at data[len], although this is not very + * useful when the string holds binary data rather than text. + * maxlen is the allocated size in bytes of 'data', i.e. the maximum + * string size (including the terminating '\0' char) that we can + * currently store in 'data' without having to reallocate + * more space. We must always have maxlen > len. + * + * An exception occurs if we failed to allocate enough memory for the string + * buffer. In that case data points to a statically allocated empty string, + * and len = maxlen = 0. + *------------------------- + */ +typedef struct PQExpBufferData +{ + char *data; + size_t len; + size_t maxlen; +} PQExpBufferData; + +typedef PQExpBufferData *PQExpBuffer; + +/*------------------------ + * Test for a broken (out of memory) PQExpBuffer. + * When a buffer is "broken", all operations except resetting or deleting it + * are no-ops. + *------------------------ + */ +#define PQExpBufferBroken(str) \ + ((str) == NULL || (str)->maxlen == 0) + +/*------------------------ + * Same, but for use when using a static or local PQExpBufferData struct. + * For that, a null-pointer test is useless and may draw compiler warnings. + *------------------------ + */ +#define PQExpBufferDataBroken(buf) \ + ((buf).maxlen == 0) + +/*------------------------ + * Initial size of the data buffer in a PQExpBuffer. + * NB: this must be large enough to hold error messages that might + * be returned by PQrequestCancel(). + *------------------------ + */ +#define INITIAL_EXPBUFFER_SIZE 256 + +/*------------------------ + * There are two ways to create a PQExpBuffer object initially: + * + * PQExpBuffer stringptr = createPQExpBuffer(); + * Both the PQExpBufferData and the data buffer are malloc'd. + * + * PQExpBufferData string; + * initPQExpBuffer(&string); + * The data buffer is malloc'd but the PQExpBufferData is presupplied. + * This is appropriate if the PQExpBufferData is a field of another + * struct. + *------------------------- + */ + +/*------------------------ + * createPQExpBuffer + * Create an empty 'PQExpBufferData' & return a pointer to it. + */ +extern PQExpBuffer createPQExpBuffer(void); + +/*------------------------ + * initPQExpBuffer + * Initialize a PQExpBufferData struct (with previously undefined contents) + * to describe an empty string. + */ +extern void initPQExpBuffer(PQExpBuffer str); + +/*------------------------ + * To destroy a PQExpBuffer, use either: + * + * destroyPQExpBuffer(str); + * free()s both the data buffer and the PQExpBufferData. + * This is the inverse of createPQExpBuffer(). + * + * termPQExpBuffer(str) + * free()s the data buffer but not the PQExpBufferData itself. + * This is the inverse of initPQExpBuffer(). + * + * NOTE: some routines build up a string using PQExpBuffer, and then + * release the PQExpBufferData but return the data string itself to their + * caller. At that point the data string looks like a plain malloc'd + * string. + */ +extern void destroyPQExpBuffer(PQExpBuffer str); +extern void termPQExpBuffer(PQExpBuffer str); + +/*------------------------ + * resetPQExpBuffer + * Reset a PQExpBuffer to empty + * + * Note: if possible, a "broken" PQExpBuffer is returned to normal. + */ +extern void resetPQExpBuffer(PQExpBuffer str); + +/*------------------------ + * enlargePQExpBuffer + * Make sure there is enough space for 'needed' more bytes in the buffer + * ('needed' does not include the terminating null). + * + * Returns 1 if OK, 0 if failed to enlarge buffer. (In the latter case + * the buffer is left in "broken" state.) + */ +extern int enlargePQExpBuffer(PQExpBuffer str, size_t needed); + +/*------------------------ + * printfPQExpBuffer + * Format text data under the control of fmt (an sprintf-like format string) + * and insert it into str. More space is allocated to str if necessary. + * This is a convenience routine that does the same thing as + * resetPQExpBuffer() followed by appendPQExpBuffer(). + */ +extern void printfPQExpBuffer(PQExpBuffer str, const char *fmt,...) pg_attribute_printf(2, 3); + +/*------------------------ + * appendPQExpBuffer + * Format text data under the control of fmt (an sprintf-like format string) + * and append it to whatever is already in str. More space is allocated + * to str if necessary. This is sort of like a combination of sprintf and + * strcat. + */ +extern void appendPQExpBuffer(PQExpBuffer str, const char *fmt,...) pg_attribute_printf(2, 3); + +/*------------------------ + * appendPQExpBufferStr + * Append the given string to a PQExpBuffer, allocating more space + * if necessary. + */ +extern void appendPQExpBufferStr(PQExpBuffer str, const char *data); + +/*------------------------ + * appendPQExpBufferChar + * Append a single byte to str. + * Like appendPQExpBuffer(str, "%c", ch) but much faster. + */ +extern void appendPQExpBufferChar(PQExpBuffer str, char ch); + +/*------------------------ + * appendBinaryPQExpBuffer + * Append arbitrary binary data to a PQExpBuffer, allocating more space + * if necessary. + */ +extern void appendBinaryPQExpBuffer(PQExpBuffer str, + const char *data, size_t datalen); + +#endif /* PQEXPBUFFER_H */ -- cgit v1.1