diff options
Diffstat (limited to 'bin')
| -rw-r--r-- | bin/mi5.awk | 137 |
1 files changed, 102 insertions, 35 deletions
diff --git a/bin/mi5.awk b/bin/mi5.awk index 6e3a7ead..14f2ff2b 100644 --- a/bin/mi5.awk +++ b/bin/mi5.awk @@ -1,69 +1,136 @@ # Crude m4 preprocessor BEGIN { - mac = 0 + self = "mi5" + + # You can change any of these, but while changing these is still relatively + # sane... if (!length(open)) open = "<%" if (!length(shut)) shut = "%>" + + # ... changing these probably isn't, and should compel you to rethink your + # code, or quite possibly your entire life thus far. + if (!length(quote)) + quote = "`" + if (!length(unquote)) + unquote = "'" + if (!length(dnl)) + dnl = "dnl" +} + +# Fatal error function +function fatal(str) { + printf "%s: %s\n", self, str | "cat >&2" + exit(1) } # Print an m4 opener as the first byte -NR == 1 { printf "`" } +NR == 1 { printf "%s", quote } # Blocks -NF == 1 && $1 == open && !mac++ { - printf "'" +NF == 1 && $1 == open && !bmac++ { + printf "%s", unquote next } -NF == 1 && $1 == shut && mac-- { - printf "`" +NF == 1 && $1 == shut && bmac-- { + printf "%s", quote next } # If in a block, print each line with any content on it after stripping leading # and trailing whitespace -mac && NF { - sub(/^ */, "") - sub(/ *$/, "") +bmac && NF { + gsub(/(^ +| +$)/, "") print $0 "dnl" } # If not in a block, look for inlines to process -!mac { +!bmac { - # We'll empty one variable into another + # We'll parse one variable into another... src = $0 dst = "" - # As long as there's a pair of opening and closing tags - while ((ind = index(src, open)) && index(src, shut) > ind) { + # Crude and slow, clansman. Your parser was no better than that of a clumsy + # child. + for (i = 1; i <= length(src); ) { - # Read up to opening tag into seg, shift from src - seg = substr(src, 1, ind - 1) - src = substr(src, ind) + # Inline macro expansion: commented + if (iquo) { - # Escape quote closer and add to dst - gsub(/'/, "''`", seg) - dst = dst seg + # Look for end of comment and tip flag accordingly + if (substr(src, i, length(unquote)) == unquote) + iquo = 0 + } - # Read up to closing tag into seg, shift from src - ind = index(src, shut) - seg = substr(src, length(open) + 1, ind - length(shut) - 1) - src = substr(src, ind + length(shut)) + # Inline macro expansion + else if (imac) { - # Translate tags to quote open and close and add to dst - sub(/^ */, "'", seg) - sub(/ *$/, "`", seg) - dst = dst seg - } + # Close the current inline macro expansion if a close tag is found + # (in m4 terms: open a new quote), looking ahead past any spaces + # from this point first + for (j = i; substr(src, j, 1) ~ /[ \t]/; j++) + continue + if (substr(src, j, length(shut)) == shut) { + dst = dst quote + i = j + i += length(shut) + imac = 0 + continue + } + + # Look for start of comment and tip flag accordingly + if (substr(src, i, length(quote)) == quote) + iquo = 1 + } + + # Plain text mode + else { - # Escape quote closers in whatever's left - gsub(/'/, "''`", src) + # Open a new inline macro expansion if an open tag is found (in m4 + # terms: close the quote), and then look ahead past any spaces from + # that point afterward + if (substr(src, i, length(open)) == open) { + dst = dst unquote + imac = 1 + for (i += length(open); substr(src, i, 1) ~ /[ \t]/; i++) + continue + continue + } - # Tack that onto the end, and print it - dst = dst src - print dst + # Escape quote terminators + if (substr(src, i, length(unquote)) == unquote) { + + # Dear Mr. President. There are too many variables nowadays. + # Please eliminate three. I am NOT a crackpot. + dst = dst unquote unquote quote + + i += length(unquote) + continue + } + } + + # If we got down here, we can just add the next character and move on + dst = dst substr(src, i, 1) + i += 1 + } + + # If we're still in a macro expansion or quote by this point, something's + # wrong; say so and stop, rather than print anything silly. + if (iquo) + fatal("Unterminated inline quote"); + else if (imac) + fatal("Unterminated inline macro"); + else + print dst } -# Print an m4 closer and newline deleter as the last bytes -END { print "'dnl" } +# Print an m4 closer and newline deleter as the last bytes if we've correctly +# stopped all our blocks +END { + if (bmac) + fatal("Unterminated block macro"); + else + print unquote dnl +} |