1 files changed, 368 insertions, 0 deletions
diff --git a/src/bin/psql/mainloop.c b/src/bin/psql/mainloop.c
new file mode 100644
index 00000000000..2f38ffbcff9
--- /dev/null
+++ b/src/bin/psql/mainloop.c
@@ -0,0 +1,368 @@
+#include <config.h>
+#include <c.h>
+#include "mainloop.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <pqexpbuffer.h>
+
+#include "settings.h"
+#include "prompt.h"
+#include "input.h"
+#include "common.h"
+#include "command.h"
+
+
+
+/* MainLoop()
+ * Main processing loop for reading lines of input
+ *	and sending them to the backend.
+ *
+ * This loop is re-entrant. May be called by \i command
+ *	which reads input from a file.
+ */
+int
+MainLoop(PsqlSettings *pset, FILE *source)
+{
+    PQExpBuffer	query_buf;		/* buffer for query being accumulated */
+    char	*line;			/* current line of input */
+    char	*xcomment;		/* start of extended comment */
+    int		len;			/* length of the line */
+    int		successResult = EXIT_SUCCESS;
+    backslashResult slashCmdStatus;
+
+    bool	eof = false;	/* end of our command input? */
+    bool	success;
+    char	in_quote;		/* == 0 for no in_quote */
+    bool	was_bslash;		/* backslash */
+    int		paren_level;
+    unsigned int query_start;
+
+    int i, prevlen, thislen;
+
+    /* Save the prior command source */
+    FILE	*prev_cmd_source;
+    bool	prev_cmd_interactive;
+
+    bool die_on_error;
+    const char *interpol_char;
+
+
+    /* Save old settings */
+    prev_cmd_source = pset->cur_cmd_source;
+    prev_cmd_interactive = pset->cur_cmd_interactive;
+
+    /* Establish new source */
+    pset->cur_cmd_source = source;
+    pset->cur_cmd_interactive = ((source == stdin) && !pset->notty);
+
+
+    query_buf = createPQExpBuffer();
+    if (!query_buf) {
+	perror("createPQExpBuffer");
+	exit(EXIT_FAILURE);
+    }
+
+    xcomment = NULL;
+    in_quote = 0;
+    paren_level = 0;
+    slashCmdStatus = CMD_UNKNOWN;		/* set default */
+
+
+    /* main loop to get queries and execute them */
+    while (!eof)
+    {
+	if (slashCmdStatus == CMD_NEWEDIT)
+	{
+	    /*
+	     * just returned from editing the line? then just copy to the
+	     * input buffer
+	     */
+	    line = strdup(query_buf->data);
+	    resetPQExpBuffer(query_buf);
+	    /* reset parsing state since we are rescanning whole query */
+	    xcomment = NULL;
+	    in_quote = 0;
+	    paren_level = 0;
+	}
+	else
+	{
+	    /*
+	     * otherwise, set interactive prompt if necessary
+	     * and get another line
+	     */
+	    if (pset->cur_cmd_interactive)
+	    {
+		int prompt_status;
+		
+		if (in_quote && in_quote == '\'')
+		    prompt_status = PROMPT_SINGLEQUOTE;
+		else if (in_quote && in_quote == '"')
+		    prompt_status= PROMPT_DOUBLEQUOTE;
+		else if (xcomment != NULL)
+		    prompt_status = PROMPT_COMMENT;
+		else if (query_buf->len > 0)
+		    prompt_status = PROMPT_CONTINUE;
+		else
+		    prompt_status = PROMPT_READY;
+
+		line = gets_interactive(get_prompt(pset, prompt_status));
+	    }
+	    else
+		line = gets_fromFile(source);
+	}
+
+
+	/* Setting these will not have effect until next line */
+	die_on_error = GetVariableBool(pset->vars, "die_on_error");
+	interpol_char = GetVariable(pset->vars, "sql_interpol");;
+
+
+	/*
+	 * query_buf holds query already accumulated.  line is the malloc'd
+	 * new line of input (note it must be freed before looping around!)
+	 * query_start is the next command start location within the line.
+	 */
+
+	/* No more input.  Time to quit, or \i done */
+	if (line == NULL || (!pset->cur_cmd_interactive && *line == '\0'))
+	{						
+	    if (GetVariableBool(pset->vars, "echo") && !GetVariableBool(pset->vars, "quiet"))
+		puts("EOF");
+	    eof = true;
+	    continue;
+	}
+
+	/* not currently inside an extended comment? */
+	if (xcomment)
+	    xcomment = line;
+
+
+	/* strip trailing backslashes, they don't have a clear meaning */
+	while (1) {
+	    char * cp = strrchr(line, '\\');
+	    if (cp && (*(cp + 1) == '\0'))
+		*cp = '\0';
+	    else
+		break;
+	}
+
+		
+	/* echo back if input is from file and flag is set */
+	if (!pset->cur_cmd_interactive && GetVariableBool(pset->vars, "echo"))
+	    fprintf(stderr, "%s\n", line);
+
+
+	/* interpolate variables into SQL */
+	len = strlen(line);
+	thislen = PQmblen(line);
+
+	for (i = 0; line[i]; i += (thislen = PQmblen(&line[i])) ) {
+	    if (interpol_char && interpol_char[0] != '\0' && interpol_char[0] == line[i]) {
+		size_t in_length, out_length;
+		const char * value;
+		char * new;
+		bool closer; /* did we have a closing delimiter or just an end of line? */
+
+		in_length = strcspn(&line[i+thislen], interpol_char);
+		closer = line[i + thislen + in_length] == line[i];
+		line[i + thislen + in_length] = '\0';
+		value = interpolate_var(&line[i + thislen], pset);
+		out_length = strlen(value);
+
+		new = malloc(len + out_length - (in_length + (closer ? 2 : 1)) + 1);
+		if (!new) {
+		    perror("malloc");
+		    exit(EXIT_FAILURE);
+		}
+
+		new[0] = '\0';
+		strncat(new, line, i);
+		strcat(new, value);
+		if (closer)
+		    strcat(new, line + i + 2 + in_length);
+
+		free(line);
+		line = new;
+		i += out_length;
+	    }
+	}
+
+	/* nothing left on line? then ignore */
+	if (line[0] == '\0') {
+	    free(line);
+	    continue;
+	}
+
+	slashCmdStatus = CMD_UNKNOWN;
+
+	len = strlen(line);
+	query_start = 0;
+
+	/*
+	 * Parse line, looking for command separators.
+	 *
+	 * The current character is at line[i], the prior character at
+	 * line[i - prevlen], the next character at line[i + thislen].
+	 */
+	prevlen = 0;
+        thislen = (len > 0) ? PQmblen(line) : 0;
+
+#define ADVANCE_1  (prevlen = thislen, i += thislen, thislen = PQmblen(line+i))
+
+	success = true;
+	for (i = 0; i < len; ADVANCE_1) {
+	    if (!success && die_on_error)
+		break;
+
+	
+	    /* was the previous character a backslash? */
+	    if (i > 0 && line[i - prevlen] == '\\')
+		was_bslash = true;
+	    else
+		was_bslash = false;
+
+    
+	    /* in quote? */
+	    if (in_quote) {
+		/* end of quote */
+		if (line[i] == in_quote && !was_bslash)
+		    in_quote = '\0';
+	    }
+
+	    /* start of quote */
+	    else if (line[i] == '\'' || line[i] == '"')
+		in_quote = line[i];
+
+	    /* in extended comment? */
+	    else if (xcomment != NULL) {
+		if (line[i] == '*' && line[i + thislen] == '/') {
+		    xcomment = NULL;
+		    ADVANCE_1;
+		}
+	    }
+   
+	    /* start of extended comment? */
+	    else if (line[i] == '/' && line[i + thislen] == '*') {
+		xcomment = &line[i];
+		ADVANCE_1;
+	    }
+
+	    /* single-line comment? truncate line */
+	    else if ((line[i] == '-' && line[i + thislen] == '-') ||
+		     (line[i] == '/' && line[i + thislen] == '/'))
+	    {
+		line[i] = '\0';		/* remove comment */
+		break;
+	    }
+
+	    /* count nested parentheses */
+	    else if (line[i] == '(')
+		paren_level++;
+
+	    else if (line[i] == ')' && paren_level > 0)
+		paren_level--;
+
+	    /* semicolon? then send query */
+	    else if (line[i] == ';' && !was_bslash && paren_level==0) {
+		line[i] = '\0';
+		/* is there anything else on the line? */
+		if (line[query_start + strspn(line + query_start, " \t")]!='\0') {
+		    /* insert a cosmetic newline, if this is not the first line in the buffer */
+		    if (query_buf->len > 0)
+			appendPQExpBufferChar(query_buf, '\n');
+		    /* append the line to the query buffer */
+		    appendPQExpBufferStr(query_buf, line + query_start);
+		}
+
+		/* execute query */
+		success = SendQuery(pset, query_buf->data);
+
+		resetPQExpBuffer(query_buf);
+		query_start = i + thislen;
+	    }
+
+	    /* backslash command */
+	    else if (was_bslash) {
+		const char * end_of_cmd = NULL;
+
+		line[i - prevlen] = '\0'; /* overwrites backslash */
+
+		/* is there anything else on the line? */
+		if (line[query_start + strspn(line + query_start, " \t")]!='\0') {
+		    /* insert a cosmetic newline, if this is not the first line in the buffer */
+		    if (query_buf->len > 0)
+			appendPQExpBufferChar(query_buf, '\n');
+		    /* append the line to the query buffer */
+		    appendPQExpBufferStr(query_buf, line + query_start);
+		}
+
+		/* handle backslash command */
+
+		slashCmdStatus = HandleSlashCmds(pset, &line[i], query_buf, &end_of_cmd);
+
+		success = slashCmdStatus != CMD_ERROR;
+
+		if (slashCmdStatus == CMD_SEND) {
+		    success = SendQuery(pset, query_buf->data);
+		    resetPQExpBuffer(query_buf);
+		    query_start = i + thislen;
+		}
+
+		/* is there anything left after the backslash command? */
+		if (end_of_cmd) {
+		    i += end_of_cmd - &line[i];
+		    query_start = i;
+		}
+		else
+		    break;
+	    }
+	}
+
+
+	if (!success && die_on_error && !pset->cur_cmd_interactive) {
+	    successResult = EXIT_USER;
+	    break;
+	}
+
+
+	if (slashCmdStatus == CMD_TERMINATE) {
+	    successResult = EXIT_SUCCESS;
+	    break;
+	}
+
+
+	/* Put the rest of the line in the query buffer. */
+	if (line[query_start + strspn(line + query_start, " \t")]!='\0') {
+	    if (query_buf->len > 0)
+		appendPQExpBufferChar(query_buf, '\n');
+	    appendPQExpBufferStr(query_buf, line + query_start);
+	}
+
+	free(line);
+
+
+	/* In single line mode, send off the query if any */
+	if (query_buf->data[0] != '\0' && GetVariableBool(pset->vars, "singleline")) {
+	    success = SendQuery(pset, query_buf->data);
+	    resetPQExpBuffer(query_buf);
+	}
+	    
+
+	/* Have we lost the db connection? */
+	if (pset->db == NULL && !pset->cur_cmd_interactive) {
+	    successResult = EXIT_BADCONN;
+	    break;
+	}
+    }							/* while */
+
+    destroyPQExpBuffer(query_buf);
+
+    pset->cur_cmd_source = prev_cmd_source;
+    pset->cur_cmd_interactive = prev_cmd_interactive;
+
+    return successResult;
+}	/* MainLoop() */
+