fe-print.c

来自「PostgreSQL7.4.6 for Linux」· C语言 代码 · 共 747 行 · 第 1/2 页

/*-------------------------------------------------------------------------
 *
 * fe-print.c
 *	  functions for pretty-printing query results
 *
 * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * These functions were formerly part of fe-exec.c, but they
 * didn't really belong there.
 *
 * IDENTIFICATION
 *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-print.c,v 1.48 2003/08/04 02:40:20 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#include "postgres_fe.h"

#include <signal.h>

#ifdef WIN32
#include "win32.h"
#else
#include <unistd.h>
#include <sys/ioctl.h>
#endif

#ifdef HAVE_TERMIOS_H
#include <termios.h>
#else
#ifndef WIN32
#include <sys/termios.h>
#endif
#endif

#include "libpq-fe.h"
#include "libpq-int.h"
#include "pqsignal.h"


static void do_field(const PQprintOpt *po, const PGresult *res,
		 const int i, const int j, const int fs_len,
		 char **fields,
		 const int nFields, const char **fieldNames,
		 unsigned char *fieldNotNum, int *fieldMax,
		 const int fieldMaxLen, FILE *fout);
static char *do_header(FILE *fout, const PQprintOpt *po, const int nFields,
	  int *fieldMax, const char **fieldNames, unsigned char *fieldNotNum,
		  const int fs_len, const PGresult *res);
static void output_row(FILE *fout, const PQprintOpt *po, const int nFields, char **fields,
		   unsigned char *fieldNotNum, int *fieldMax, char *border,
		   const int row_index);
static void fill(int length, int max, char filler, FILE *fp);

/*
 * PQprint()
 *
 * Format results of a query for printing.
 *
 * PQprintOpt is a typedef (structure) that containes
 * various flags and options. consult libpq-fe.h for
 * details
 *
 * This function should probably be removed sometime since psql
 * doesn't use it anymore. It is unclear to what extend this is used
 * by external clients, however.
 */

void
PQprint(FILE *fout,
		const PGresult *res,
		const PQprintOpt *po)
{
	int			nFields;

	nFields = PQnfields(res);

	if (nFields > 0)
	{							/* only print rows with at least 1 field.  */
		int			i,
					j;
		int			nTups;
		int		   *fieldMax = NULL;	/* in case we don't use them */
		unsigned char *fieldNotNum = NULL;
		char	   *border = NULL;
		char	  **fields = NULL;
		const char **fieldNames;
		int			fieldMaxLen = 0;
		int			numFieldName;
		int			fs_len = strlen(po->fieldSep);
		int			total_line_length = 0;
		int			usePipe = 0;
		pqsigfunc	oldsigpipehandler = NULL;
		char	   *pagerenv;

#ifdef TIOCGWINSZ
		struct winsize screen_size;

#else
		struct winsize
		{
			int			ws_row;
			int			ws_col;
		}			screen_size;
#endif

		nTups = PQntuples(res);
		if (!(fieldNames = (const char **) calloc(nFields, sizeof(char *))))
		{
			perror("calloc");
			exit(1);
		}
		if (!(fieldNotNum = (unsigned char *) calloc(nFields, 1)))
		{
			perror("calloc");
			exit(1);
		}
		if (!(fieldMax = (int *) calloc(nFields, sizeof(int))))
		{
			perror("calloc");
			exit(1);
		}
		for (numFieldName = 0;
			 po->fieldName && po->fieldName[numFieldName];
			 numFieldName++)
			;
		for (j = 0; j < nFields; j++)
		{
			int			len;
			const char *s = (j < numFieldName && po->fieldName[j][0]) ?
			po->fieldName[j] : PQfname(res, j);

			fieldNames[j] = s;
			len = s ? strlen(s) : 0;
			fieldMax[j] = len;
			len += fs_len;
			if (len > fieldMaxLen)
				fieldMaxLen = len;
			total_line_length += len;
		}

		total_line_length += nFields * strlen(po->fieldSep) + 1;

		if (fout == NULL)
			fout = stdout;
		if (po->pager && fout == stdout
#ifndef WIN32
			&&
			isatty(fileno(stdin)) &&
			isatty(fileno(stdout))
#endif
			)
		{
			/*
			 * If we think there'll be more than one screen of output, try
			 * to pipe to the pager program.
			 */
#ifdef TIOCGWINSZ
			if (ioctl(fileno(stdout), TIOCGWINSZ, &screen_size) == -1 ||
				screen_size.ws_col == 0 ||
				screen_size.ws_row == 0)
			{
				screen_size.ws_row = 24;
				screen_size.ws_col = 80;
			}
#else
			screen_size.ws_row = 24;
			screen_size.ws_col = 80;
#endif
			pagerenv = getenv("PAGER");
			if (pagerenv != NULL &&
				pagerenv[0] != '\0' &&
				!po->html3 &&
				((po->expanded &&
				  nTups * (nFields + 1) >= screen_size.ws_row) ||
				 (!po->expanded &&
				  nTups * (total_line_length / screen_size.ws_col + 1) *
				  (1 + (po->standard != 0)) >= screen_size.ws_row -
				  (po->header != 0) *
				  (total_line_length / screen_size.ws_col + 1) * 2
				  - (po->header != 0) * 2		/* row count and newline */
				  )))
			{
#ifdef WIN32
				fout = _popen(pagerenv, "w");
#else
				fout = popen(pagerenv, "w");
#endif
				if (fout)
				{
					usePipe = 1;
#ifndef WIN32
					oldsigpipehandler = pqsignal(SIGPIPE, SIG_IGN);
#endif
				}
				else
					fout = stdout;
			}
		}

		if (!po->expanded && (po->align || po->html3))
		{
			if (!(fields = (char **) calloc(nFields * (nTups + 1), sizeof(char *))))
			{
				perror("calloc");
				exit(1);
			}
		}
		else if (po->header && !po->html3)
		{
			if (po->expanded)
			{
				if (po->align)
					fprintf(fout, "%-*s%s Value\n",
							fieldMaxLen - fs_len, "Field", po->fieldSep);
				else
					fprintf(fout, "%s%sValue\n", "Field", po->fieldSep);
			}
			else
			{
				int			len = 0;

				for (j = 0; j < nFields; j++)
				{
					const char *s = fieldNames[j];

					fputs(s, fout);
					len += strlen(s) + fs_len;
					if ((j + 1) < nFields)
						fputs(po->fieldSep, fout);
				}
				fputc('\n', fout);
				for (len -= fs_len; len--; fputc('-', fout));
				fputc('\n', fout);
			}
		}
		if (po->expanded && po->html3)
		{
			if (po->caption)
				fprintf(fout, "<centre><h2>%s</h2></centre>\n", po->caption);
			else
				fprintf(fout,
						"<centre><h2>"
						"Query retrieved %d rows * %d fields"
						"</h2></centre>\n",
						nTups, nFields);
		}
		for (i = 0; i < nTups; i++)
		{
			if (po->expanded)
			{
				if (po->html3)
					fprintf(fout,
						  "<table %s><caption align=high>%d</caption>\n",
							po->tableOpt ? po->tableOpt : "", i);
				else
					fprintf(fout, "-- RECORD %d --\n", i);
			}
			for (j = 0; j < nFields; j++)
				do_field(po, res, i, j, fs_len, fields, nFields,
						 fieldNames, fieldNotNum,
						 fieldMax, fieldMaxLen, fout);
			if (po->html3 && po->expanded)
				fputs("</table>\n", fout);
		}
		if (!po->expanded && (po->align || po->html3))
		{
			if (po->html3)
			{
				if (po->header)
				{
					if (po->caption)
						fprintf(fout,
						  "<table %s><caption align=high>%s</caption>\n",
								po->tableOpt ? po->tableOpt : "",
								po->caption);
					else
						fprintf(fout,
								"<table %s><caption align=high>"
								"Retrieved %d rows * %d fields"
								"</caption>\n",
						po->tableOpt ? po->tableOpt : "", nTups, nFields);
				}
				else
					fprintf(fout, "<table %s>", po->tableOpt ? po->tableOpt : "");
			}
			if (po->header)
				border = do_header(fout, po, nFields, fieldMax, fieldNames,
								   fieldNotNum, fs_len, res);
			for (i = 0; i < nTups; i++)
				output_row(fout, po, nFields, fields,
						   fieldNotNum, fieldMax, border, i);
			free(fields);
			if (border)
				free(border);
		}
		if (po->header && !po->html3)
			fprintf(fout, "(%d row%s)\n\n", PQntuples(res),
					(PQntuples(res) == 1) ? "" : "s");
		free(fieldMax);
		free(fieldNotNum);
		free((void *) fieldNames);
		if (usePipe)
		{
#ifdef WIN32
			_pclose(fout);
#else
			pclose(fout);
			pqsignal(SIGPIPE, oldsigpipehandler);
#endif
		}
		if (po->html3 && !po->expanded)
			fputs("</table>\n", fout);
	}
}


static void
do_field(const PQprintOpt *po, const PGresult *res,
		 const int i, const int j, const int fs_len,
		 char **fields,
		 const int nFields, char const ** fieldNames,
		 unsigned char *fieldNotNum, int *fieldMax,
		 const int fieldMaxLen, FILE *fout)
{

	const char *pval,
			   *p;
	int			plen;
	bool		skipit;

	plen = PQgetlength(res, i, j);
	pval = PQgetvalue(res, i, j);

	if (plen < 1 || !pval || !*pval)
	{
		if (po->align || po->expanded)
			skipit = true;
		else
		{
			skipit = false;
			goto efield;
		}
	}
	else
		skipit = false;

	if (!skipit)
	{
		if (po->align && !fieldNotNum[j])
		{
			/* Detect whether field contains non-numeric data */
			char		ch = '0';

			for (p = pval; *p; p += PQmblen(p, res->client_encoding))
			{
				ch = *p;
				if (!((ch >= '0' && ch <= '9') ||
					  ch == '.' ||
					  ch == 'E' ||
					  ch == 'e' ||
					  ch == ' ' ||
					  ch == '-'))
				{
					fieldNotNum[j] = 1;
					break;
				}
			}

			/*
			 * Above loop will believe E in first column is numeric; also,
			 * we insist on a digit in the last column for a numeric. This
			 * test is still not bulletproof but it handles most cases.
			 */