mysql2sqlite.c

/*
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

    Copyright (C) 2010 - Johannes 'josch' Schauer <josch@pyneo.org>
*/

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>


char *hexlookup = "000102030405060708090a0b0c0d0e0f"
	"101112131415161718191a1b1c1d1e1f"
	"202122232425262728292a2b2c2d2e2f"
	"303132333435363738393a3b3c3d3e3f"
	"404142434445464748494a4b4c4d4e4f"
	"505152535455565758595a5b5c5d5e5f"
	"606162636465666768696a6b6c6d6e6f"
	"707172737475767778797a7b7c7d7e7f"
	"808182838485868788898a8b8c8d8e8f"
	"909192939495969798999a9b9c9d9e9f"
	"a0a1a2a3a4a5a6a7a8a9aaabacadaeaf"
	"b0b1b2b3b4b5b6b7b8b9babbbcbdbebf"
	"c0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
	"d0d1d2d3d4d5d6d7d8d9dadbdcdddedf"
	"e0e1e2e3e4e5e6e7e8e9eaebecedeeef"
	"f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";

void fatal(char *msg, int linenum)
{
	fprintf(stderr, "%s at line %d\n", msg, linenum);
	exit(1);
}

void putchr(int c)
{
	if (fputc(c, stdout) == EOF) {
		fprintf(stderr, "cannot write output\n");
		exit(2);
	}
}

void putstr(char *c, int l)
{
	if (!fwrite(c, l, 1, stdout)) {
		fprintf(stderr, "cannot write output\n");
		exit(2);
	}
}

void putchrx(int c)
{
	int p = ((unsigned char)c)*2;
	if (fputc(hexlookup[p], stdout) == EOF || fputc(hexlookup[p+1], stdout) == EOF) {
		fprintf(stderr, "cannot write output\n");
		exit(2);
	}
}

void putstrx(char *c, int l)
{
	int i;
	int p;
	for (i = 0; i < l; i++, c++) {
		p = ((unsigned char)*c)*2;
		if (fputc(hexlookup[p], stdout) == EOF || fputc(hexlookup[p+1], stdout) == EOF) {
			fprintf(stderr, "cannot write output\n");
			exit(2);
		}
	}
}

int main(void)
{
	char * line = NULL;
	char * lineptr;
	char * endptr;
	size_t len = 0;
	ssize_t read;
	int linenum;
	char * tablename;
	int tablenamelen = 0;
	char *p;

	putstr("PRAGMA synchronous=OFF;\n"
		"PRAGMA count_changes=OFF;\n"
		"PRAGMA cache_size=2000000;\n"
		"PRAGMA journal_mode = OFF;\n"
		"BEGIN TRANSACTION;\n", 123);

	// for each line
	for (linenum = 0; (read = getline(&line, &len, stdin)) != -1; linenum++) {
		lineptr = line;

		if (read <= 15 || strncmp("INSERT INTO `", lineptr, 13)) {
			continue;
		}

		lineptr += 13;

		if (tablenamelen) {
			if (strncmp(tablename, lineptr, tablenamelen))
				fatal("expected different tablename", linenum);
		} else {
			if ((endptr = strchr(lineptr, '`')) == NULL)
				fatal("expected tablename", linenum);

			tablenamelen = endptr - lineptr;

			if (tablenamelen > 255)
				fatal("tablename too long", linenum);

			if (tablenamelen == 0)
				fatal("no tablename", linenum);

			tablename = strndup(lineptr, tablenamelen);
		}

		lineptr += tablenamelen + 1;

		if (strncmp(" VALUES (", lineptr, 9))
			fatal("expected 'VALUES ('", linenum);

		lineptr += 9;

		// for each record
		for (;;) {
			putstr("INSERT INTO '", 13);
			putstr(tablename, tablenamelen);
			putstr("' VALUES (", 10);

			// for each column
			for (;;) {
				if (*lineptr == '\'') {

					putchr('x');
					putchr('\'');

					lineptr++;

					// for each escape char
					for (;;) {
						if ((p = strpbrk(lineptr, "\\'")) == NULL)
							fatal("expected '\\' or \"'\"", linenum);

						if ((p-lineptr))
							putstrx(lineptr, (p-lineptr));

						if (*p == '\'') {
							lineptr = p;
							break;
						} else {
							switch (*(++p)) {
							case 'n':
								putchrx('\n'); break;
							case 'r':
								putchrx('\r'); break;
							case '0':
								putchrx('\0'); break;
							case '"':
							case '\\':
							case '\'':
								putchrx(*p); break;
							default:
								fatal("unknown escape character", linenum);
							}
							lineptr = ++p;
						}
					}

					putchr('\'');

					lineptr++;
				} else {
					if ((p = strpbrk(lineptr, ",)")) == NULL)
						fatal("expected ',' or ')'", linenum);

					putstr(lineptr, (p-lineptr));

					lineptr = p;
				}

				if (*lineptr == ')')
					break;

				if (*(lineptr++) != ',')
					fatal("expected ','", linenum);

				putchr(',');
			}

			putstr(");\n", 3);

			if (*(++lineptr) == ';') break;

			if (*(lineptr++) != ',')
				fatal("expected ','", linenum);

			if (*(lineptr++) != '(')
				fatal("expected '('", linenum);
		}

	}

	putstr("COMMIT TRANSACTION;\n", 20);

	if (line)
		free(line);
	return EXIT_SUCCESS;
}