Add newlines before parenthesis for a SQL mysqldump

process-mysqldump.c

// gcc -O2 -Wall -pedantic process-mysqldump.c -o process-mysqldump
// Usage: cat dump.sql | process-mysqldump
//   Or : process-mysqldump dump.sql

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>

#define BUFFER 100000

bool is_escaped(char* string, int offset) {
    if (offset == 0) {
        return false;
    } else if (string[offset - 1] == '\\') {
        return !is_escaped(string, offset - 1);
    } else {
        return false;
    }
}

bool is_insert(char* string) {
    char buffer[] = "INSERT INTO ";

    return strncmp(buffer, string, 12) == 0;
}

int main(int argc, char *argv[])
{
    FILE* file = argc > 1 ? fopen(argv[1], "rb") : stdin;

    char buffer[BUFFER];
    char* line;
    int pos;
    int parenthesis = 0;
    bool quote = false;
    bool escape = false;
    bool check_prefix = true;
    bool wasnt_insert = false;

    while (fgets(buffer, BUFFER, file) != NULL) {
        line = buffer;

        // skip non-INSERT INTO statements
        if (check_prefix && (wasnt_insert || ! is_insert(line))) {
            check_prefix = line[strlen(line) - 1] == '\n';
            wasnt_insert = ! check_prefix;
            fputs(line, stdout);
            continue;
        }

        check_prefix = line[strlen(line) - 1] == '\n';
        pos = 0;

        nullchar:
        while (line[pos] != '\0') {
            // if we are still in escape state, we need to check first char.
            if (!escape) {
                // find any character in ()'
                pos = strcspn(line, "()'\\");
            }

            if (pos > 0) {
                // print before match
                printf("%.*s", pos, line);
            }

            switch (line[pos]) {
                case '(':
                    if (!quote) {
                        if (parenthesis == 0) {
                            puts("");
                        }
                        parenthesis++;
                    }
                    if (escape) {
                        escape = false;
                    }
                    break;

                case ')':
                    if (!quote) {
                        if (parenthesis > 0) {
                            parenthesis--;
                        } else {
                            // whoops
                            puts("");
                            fputs(line, stdout);
                            fputs("Found closing parenthesis without opening one.\n", stderr);
                            exit(1);
                        }
                    }
                    if (escape) {
                        escape = false;
                    }
                    break;

                case '\\':
                    escape = !escape;
                    break;

                case '\'':
                    if (escape) {
                        escape = false;
                    } else {
                        quote = !quote;
                    }
                    break;

                case '\0':
                    goto nullchar;

                default:
                    if (escape) {
                        escape = false;
                    }
                    break;
            }

            // print char then skip it (to make sure we don’t double match)
            putchar(line[pos]);
            line = line + pos + 1;
            pos = 0;
        }
    }

    return 0;
}

process-mysqldump.php

<?php
// Usage: cat dump.sql | php process-mysqldump.php
while (false !== ($line = fgets_big_buffer())) {
    if (substr($line, 0, 6) === 'INSERT') {
        process_line($line);
    } else {
        echo $line;
    }
}
function fgets_big_buffer()
{
    $ret = fgets(STDIN, 1 * 1024 * 1024);
    if ($ret === false || $ret[strlen($ret) - 1] === "\n") {
        return $ret;
    }
    while (1) {
        $tmp = fgets(STDIN, 1 * 1024 * 1024);
        if ($tmp === false) {
            return $ret;
        }
        $ret .= $tmp;
        if ($tmp[strlen($tmp) - 1] === "\n") {
            return $ret;
        }
    }
}
function process_line($line)
{
    $length = strlen($line);
    $pos = strpos($line, ' VALUES ') + 8;
    $ret = substr($line, 0, $pos);
    $parenthesis = false;
    $quote = false;
    $escape = false;
    for ($i = $pos; $i < $length; ++ $i) {
        switch ($line[$i]) {
            case '(':
                if (! $quote) {
                    if ($parenthesis) {
                       throw new \Exception ( 'double open parenthesis' );
                    } else {
                        $ret .= "\n";
                        $parenthesis = true;
                    }
                }
                $escape = false;
                break;
            case ')':
                if (! $quote) {
                    if ($parenthesis) {
                        $parenthesis = false;
                    } else {
                         throw new Exception ( 'closing parenthesis without open' );
                    }
                }
                $escape = false;
                break;
            case '\\':
                $escape = ! $escape;
                break;
            case "'":
                if ($escape) {
                    $escape = false;
                } else {
                    $quote = ! $quote;
                }
                break;
            default:
                $escape = false;
                break;
        }
        $ret .= $line[$i];
        $to = strcspn($line, '()\\\'', $i + 1)-1;
        if ($to > 0) {
            $ret .= substr($line, $i + 1, $to);
            $i += ($to);
        }
    }
    echo $ret;
}