diff options
| -rw-r--r-- | bin/hi.c | 283 | ||||
| -rw-r--r-- | bin/man1/hi.1 | 62 |
2 files changed, 345 insertions, 0 deletions
diff --git a/bin/hi.c b/bin/hi.c new file mode 100644 index 00000000..35188655 --- /dev/null +++ b/bin/hi.c @@ -0,0 +1,283 @@ +/* Copyright (C) 2019 June McEnroe <june@causal.agency> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <err.h> +#include <regex.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <sysexits.h> +#include <unistd.h> + +#define ARRAY_LEN(a) (sizeof(a) / sizeof(a[0])) + +enum Class { + Normal, + Keyword, + Macro, + Comment, + String, + ClassCount, +}; + +struct Syntax { + enum Class class; + int flags; + const char *pattern; +}; + +// FIXME: Looks like [[:<:]] [[:>:]] are not supported on GNU. +static const struct Syntax CSyntax[] = { + { Keyword, 0, "[[:<:]](enum|struct|typedef|union)[[:>:]]" }, + { Keyword, 0, "[[:<:]](const|inline|static)[[:>:]]" }, + { Keyword, 0, "[[:<:]](do|else|for|if|switch|while)[[:>:]]" }, + { Keyword, 0, "[[:<:]](break|continue|goto|return)[[:>:]]" }, + { Keyword, 0, "[[:<:]](case|default)[[:>:]]" }, + { Macro, REG_NEWLINE, "^#.*" }, + { String, REG_NEWLINE, "<[^[:blank:]=]*>" }, + { Comment, REG_NEWLINE, "//.*" }, + { Comment, REG_ENHANCED, "/\\*.*?\\*/" }, // FIXME: Darwin-only. + { String, REG_NEWLINE, "[LUu]?'([^']|\\\\')*'" }, + { String, REG_NEWLINE, "([LUu]|u8)?\"([^\"]|\\\\\")*\"" }, +}; + +static const struct Language { + const char *name; + const char *pattern; + const struct Syntax *syntax; + size_t len; +} Languages[] = { + { "c", "\\.[ch]$", CSyntax, ARRAY_LEN(CSyntax) }, +}; + +static regex_t compile(const char *pattern, int flags) { + regex_t regex; + int error = regcomp(®ex, pattern, REG_EXTENDED | flags); + if (!error) return regex; + char buf[256]; + regerror(error, ®ex, buf, sizeof(buf)); + errx(EX_SOFTWARE, "regcomp: %s: %s", buf, pattern); +} + +static void highlight(struct Language lang, enum Class *hi, const char *str) { + for (size_t i = 0; i < lang.len; ++i) { + regex_t regex = compile(lang.syntax[i].pattern, lang.syntax[i].flags); + regmatch_t match = {0}; + for (size_t offset = 0; str[offset]; offset += match.rm_eo) { + int error = regexec( + ®ex, &str[offset], 1, &match, offset ? REG_NOTBOL : 0 + ); + if (error == REG_NOMATCH) break; + if (error) errx(EX_SOFTWARE, "regexec: %d", error); + for (regoff_t j = match.rm_so; j < match.rm_eo; ++j) { + hi[offset + j] = lang.syntax[i].class; + } + } + regfree(®ex); + } +} + +typedef void HeaderFn(const char *path); +typedef void OutputFn(enum Class class, const char *str, size_t len); + +enum SGR { + Reset, Bold, + Black = 30, Red, Green, Yellow, Blue, Magenta, Cyan, White, Default, +}; + +static const enum SGR Style[ClassCount][2] = { + [Normal] = { Reset, Default }, + [Keyword] = { Reset, White }, + [Macro] = { Reset, Green }, + [Comment] = { Reset, Blue }, + [String] = { Reset, Cyan }, +}; + +static void ansiOutput(enum Class class, const char *str, size_t len) { + // Style each line separately, otherwise less -R won't look right. + while (len) { + size_t line = strcspn(str, "\n") + 1; + if (line > len) line = len; + printf( + "\x1B[%d;%dm%.*s\x1B[%dm", + Style[class][0], Style[class][1], (int)line, str, Style[class][0] + ); + str += line; + len -= line; + } +} + +static void htmlHeader(const char *path) { + (void)path; + printf("<pre>"); +} +static void htmlFooter(const char *path) { + (void)path; + printf("</pre>\n"); +} + +static void htmlEscape(const char *str, size_t len) { + while (len) { + size_t run = strcspn(str, "&<>"); + if (run > len) run = len; + switch (str[0]) { + break; case '&': run = 1; printf("&"); + break; case '<': run = 1; printf("<"); + break; case '>': run = 1; printf(">"); + break; default: printf("%.*s", (int)run, str); + } + str += run; + len -= run; + } +} + +static const char *ClassName[ClassCount] = { + [Normal] = "Normal", + [Keyword] = "Keyword", + [Macro] = "Macro", + [Comment] = "Comment", + [String] = "String", +}; + +static void htmlOutput(enum Class class, const char *str, size_t len) { + printf("<span class=\"hi %s\">", ClassName[class]); + htmlEscape(str, len); + printf("</span>"); +} + +static void htmlDocumentHeader(const char *path) { + const char *slash = strrchr(path, '/'); + if (slash) path = &slash[1]; + printf("<!DOCTYPE html>\n<title>"); + htmlEscape(path, strlen(path)); + printf( + "</title>\n" + "<style>\n" + ".hi.Keyword { color: dimgray; }\n" + ".hi.Macro { color: green; }\n" + ".hi.Comment { color: navy; }\n" + ".hi.String { color: teal; }\n" + "</style>\n" + ); + htmlHeader(path); +} + +static const struct Format { + const char *name; + OutputFn *output; + HeaderFn *header; + HeaderFn *footer; +} Formats[] = { + { "ansi", ansiOutput, NULL, NULL }, + { "html", htmlOutput, htmlHeader, htmlFooter }, + { "html-document", htmlOutput, htmlDocumentHeader, htmlFooter }, +}; + +int main(int argc, char *argv[]) { + bool check = false; + const struct Language *lang = NULL; + const struct Format *format = NULL; + + int opt; + while (0 < (opt = getopt(argc, argv, "cf:l:"))) { + switch (opt) { + break; case 'c': check = true; + break; case 'f': { + for (size_t i = 0; i < ARRAY_LEN(Formats); ++i) { + if (strcmp(optarg, Formats[i].name)) continue; + format = &Formats[i]; + break; + } + if (!format) errx(EX_USAGE, "no such format %s", optarg); + } + break; case 'l': { + for (size_t i = 0; i < ARRAY_LEN(Languages); ++i) { + if (strcmp(optarg, Languages[i].name)) continue; + lang = &Languages[i]; + break; + } + if (!lang) errx(EX_USAGE, "no such language %s", optarg); + } + break; default: return EX_USAGE; + } + } + + if (check) { + for (size_t i = 0; i < ARRAY_LEN(Languages); ++i) { + regex_t regex = compile(Languages[i].pattern, REG_NOSUB); + regfree(®ex); + for (size_t j = 0; j < Languages[i].len; ++j) { + regex = compile(Languages[i].syntax[j].pattern, REG_NOSUB); + regfree(®ex); + } + } + return EX_OK; + } + + const char *path = "(stdin)"; + FILE *file = stdin; + if (optind < argc) { + path = argv[optind]; + file = fopen(path, "r"); + if (!file) err(EX_NOINPUT, "%s", path); + } + + if (!lang) { + for (size_t i = 0; i < ARRAY_LEN(Languages); ++i) { + regex_t regex = compile(Languages[i].pattern, REG_NOSUB); + bool match = !regexec(®ex, path, 0, NULL, 0); + regfree(®ex); + if (match) { + lang = &Languages[i]; + break; + } + } + if (!lang) errx(EX_USAGE, "cannot infer language for %s", path); + } + if (!format) format = &Formats[0]; + + size_t len = 32 * 1024; + if (file != stdin) { + struct stat stat; + int error = fstat(fileno(file), &stat); + if (error) err(EX_IOERR, "fstat"); + len = stat.st_size; + } + + char *str = malloc(len + 1); + if (!str) err(EX_OSERR, "malloc"); + + len = fread(str, 1, len, file); + if (ferror(file)) err(EX_IOERR, "fread"); + str[len] = '\0'; + + enum Class *hi = calloc(len, sizeof(*hi)); + if (!hi) err(EX_OSERR, "calloc"); + + highlight(*lang, hi, str); + + if (format->header) format->header(path); + size_t run = 0; + for (size_t i = 0; i < len; i += run) { + for (run = 0; i + run < len; ++run) { + if (hi[i + run] != hi[i]) break; + } + format->output(hi[i], &str[i], run); + } + if (format->footer) format->footer(path); +} diff --git a/bin/man1/hi.1 b/bin/man1/hi.1 new file mode 100644 index 00000000..5ed72061 --- /dev/null +++ b/bin/man1/hi.1 @@ -0,0 +1,62 @@ +.Dd February 6, 2019 +.Dt HI 1 +.Os +. +.Sh NAME +.Nm hi +.Nd syntax highlighter +. +.Sh SYNOPSIS +.Nm +.Op Fl f Ar format +.Op Fl l Ar lang +.Op Ar file +.Nm +.Fl c +. +.Sh DESCRIPTION +.Nm +highlights the contents of a +.Ar file +or standard input +and formats it +on standard output. +. +.Pp +The arguments are as follows: +.Bl -tag -width Ds +.It Fl c +Compile all regular expressions and exit. +.It Fl f Ar format +Set the output format. +The default +.Ar format +is +.Cm ansi . +.It Fl l Ar lang +Set the input language. +If a +.Ar file +is provided, +.Ar lang +may be inferred from its name. +.El +. +.Pp +The following languages are supported: +.Cm c . +. +.Pp +The output formats are as follows: +.Bl -tag -width "html-document" +.It Cm ansi +ANSI terminal escape codes. +.It Cm html +HTML +.Sy <pre> +fragment with +.Sy <span> +classes. +.It Cm html-document +HTML document with default styles. +.El |