- From:
- Tracey Emery <tracey@traceyemery.net>
- Subject:
- Re: [RFC] template system for gotwebd
- To:
- Omar Polo <op@omarpolo.com>
- Cc:
- gameoftrees@openbsd.org
- Date:
- Thu, 22 Sep 2022 07:43:02 -0600
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[RFC] template system for gotwebd
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[RFC] template system for gotwebd
On Thu, Sep 22, 2022 at 11:44:13AM +0200, Omar Polo wrote:
> For some personal project(s) I ended up writing a small template
> """engine""" to generate HTML (but not only.) I did this because I
> found a bit of a pain to (safely) generate HTML by means of printf or
> the like. Since this has been working fine for me, I thought gotwebd
> could benefit from it too.
>
> Diff below is not intended to be committed as-is, neither to be
> reviewed or even tested, it's just for demonstration purpose: the
> added code is not used at runtime! If y'all like the direction, I can
> work on a better diff that moves the HTML generation to this template
> system.
I'll be afk a lot and gone all next week, so I wanted to throw my two
cents in really quickly. I don't hate this idea at all and it's totally
worth further discussion. I'll need to re-read this a few times to fully
grasp it, but I think templating is fine!
>
>
> How it works?
> =============
>
> At a higher level the templates are file written in a custom syntax
> which is mostly HTML except for some special constructs embedded
> within {{ ... }} or {! ... !}. Producing HTML (or anything else
> really) is achieved by defining "blocks". These blocks are turned at
> *compile time* into plain C functions that output the text via some
> provided functions.
>
> I'd like to stress the point that the templates are *compiled* into C
> and not executed at runtime, as happens with many other template
> systems.
>
> here's an example of how to define a block:
>
> {{ define gw_base(struct template *tp, const char *title) }}
> <!doctype html>
> <html>
> <head>
> <title>{{ title }}</title>
> </head>
> <body>
> {{ render tp->tp_body }}
> </body>
> </html>
> {{ end }}
>
> that gets turned into something like the following pseudo code:
>
> int
> gw_base(struct template *tp, const char *title)
> {
> /* print from <!doctype> to <title> */
> /* ... */
>
> print(htmlescape(title));
>
> /* print until <body> */
> /* ... */
>
> if (tp->tp_body(tp) == -1)
> return (-1);
>
> /* print </body></html> */
>
> return (0);
> }
>
> In short, it just turn some HTML fragments into glorified printfs, but
> providing an easy way to safely interpolate variables.
>
> It implicitly HTML-escape the variables and provides a mean to choose
> a different escape strategy case-by-case (e.g. to urlencode something
> or to *not* escape something else.) Everything is implicitly escaped,
> you have to be verbose to change/disable it.
>
> Different escaping "strategies" can be choosen as follows:
>
> {{ foo | unsafe }} aka don't escape
> {{ foo | urlescape }}
>
> There's also some small syntax for conditionals:
>
> {{ if something }}
> ...
> {{ else if x && !y }}
> ...
> {{ else }}
> ...
> {{ end }}
>
> and loops:
>
> {{ tailq-foreach rc &t->repo_commits entry }}
> ...
> {{ end }}
>
> Since these templates are turned into C code, there's a mean to inline
> some code that will be left as-is in the generated file using the
>
> {! /* code ... */ !}
>
> construct.
>
> Finally, there's a small syntax sugar for calling another block using
> the `render' keyword:
>
> {{ render another_block }}
>
>
> Pros and cons
> =============
>
> The main advantage is that it avoids very ugly sections of
>
> if (fcgi_printf(c, "...") == -1)
> goto err;
>
> Writing HTML in a separate file allows to use a proper indentation and
> makes leaving dangling tags open harder. The template system also
> implicitly discards blanks at the start of the lines, so it also
> avoids sending blanks to the browser.
>
> I'd argue that it's easier/fun to hack on these templates files rather
> than writing HTML as bits of C strings.
>
> Turning this templates into C code that gets then compiled and linked
> as part of gotwebd also avoids interpreting stuff at runtime and
> allows for the compiler to do some optimizations here and there (not
> that I think it can optimize much tho.)
>
> It's possibly more efficient than what we currently have. The
> generated code uses a sequence of puts-like and putc-like functions to
> both output the HTML and do the escaping, so it avoids the overhead of
> the implicit vasprintf in fcgi_printf and all the alloc/free we're
> currently doing to escape the strings.
>
> The interpolated strings are automatically escaped by default, instead
> of requiring to manually escaping them (and free the allocated escaped
> string.)
>
> The "compiler" uses the #line directive, just like yacc does, so
> eventual C error or warnings are reported relatively to the template
> file and not the generated code. Even the debugger shows the template
> being processed.
>
> We can probably leverage the template system to write some regress
> tests for gotwebd. The template system is "output agnostic", it just
> uses the given functions to do the output. In gotwebd the output will
> be through fastcgi, but in a hypothetical regress suite we could
> override the templates and just print plain text to standard output.
> I have not yet investigated into this, it's pure speculation.
>
> The template 'language' is very Go html/template inspired, but is
> still decently different and this can be confusing.
>
> The "compiler" is not even remotely smart, it just bashes strings
> together, and the generated code assume there's a variable in scope
> called `tp' of type `struct template', so every block needs to have an
> argument with that name and of that type.
>
> The error reporting is not great, but as it's an internal tool I don't
> think it's a big deal.
>
> The fact that trims out the blanks leads to some possible edge cases
> where we want to include a space but the template "compiler" trims it
> out. It's possible to work around it by using {{ " " }}.
>
> I have not found a clean way to integrate the template generation into
> the bsd.prog.mk infrastructure. Diff belows assumes the template
> "compiler" is in ${.CURDIR}/template/obj/template, but one can also
> not `make obj'.
>
> -*-*-
>
> Diff below includes an (incomplete) example of how we could probably
> rewrite gotweb_render_header/footer and the commits fragment. For a
> more real-life example, you can take a look at `fragments.tmpl' in
>
> https://git.omarpolo.com/?action=summary&path=galileo.git
>
> where this template system originates from.
>
>
> What do you think? Would something like this be a good addition to
> gotwebd?
>
> diff /home/op/w/gwd-template
> commit - 611e5fc2074d428e17f920dc595496af4dd0dc77
> path + /home/op/w/gwd-template
> blob - 01296896441d21b985a59ffc870ef3d3b03f4a31
> file + gotwebd/Makefile
> --- gotwebd/Makefile
> +++ gotwebd/Makefile
> @@ -1,13 +1,14 @@
> .PATH:${.CURDIR}/../lib
> +.PATH:${.CURDIR}/template
>
> -SUBDIR = libexec
> +SUBDIR = libexec template
>
> .include "../got-version.mk"
> .include "Makefile.inc"
>
> PROG = gotwebd
> SRCS = config.c sockets.c log.c gotwebd.c parse.y proc.c \
> - fcgi.c gotweb.c got_operations.c
> + fcgi.c gotweb.c got_operations.c tmpl.o
> SRCS += blame.c commit_graph.c delta.c diff.c \
> diffreg.c error.c fileindex.c object.c object_cache.c \
> object_idset.c object_parse.c opentemp.c path.c pack.c \
> @@ -19,9 +20,20 @@ SRCS += blame.c commit_graph.c delta.c diff.c \
> diff_output_edscript.c diff_patience.c bloom.c murmurhash2.c \
> worktree_open.c patch.c sigs.c date.c sockaddr.c
>
> +TEMPLATES = pages.tmpl
> +
> +.for t in ${TEMPLATES}
> +SRCS += ${t:.tmpl=.c}
> +CLEANFILES += ${t:.tmpl=.c}
> +
> +${t:.tmpl=.c}: ${t}
> + ${.CURDIR}/template/obj/template $? > $@
> +.endfor
> +
> MAN = ${PROG}.conf.5 ${PROG}.8
>
> CPPFLAGS += -I${.CURDIR}/../include -I${.CURDIR}/../lib -I${.CURDIR}
> +CPPFLAGS += -I${.CURDIR}/template/
> LDADD += -lz -levent -lutil -lm
> YFLAGS =
> DPADD = ${LIBEVENT} ${LIBUTIL}
> blob - /dev/null
> file + gotwebd/pages.tmpl
> --- /dev/null
> +++ gotwebd/pages.tmpl
> @@ -0,0 +1,195 @@
> +{!
> +
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + * Copyright (c) 2016, 2019, 2020-2022 Tracey Emery <tracey@traceyemery.net>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#include <sys/types.h>
> +#include <sys/queue.h>
> +#include <sys/uio.h>
> +
> +#include <event.h>
> +#include <stdint.h>
> +#include <imsg.h>
> +
> +#include "proc.h"
> +#include "tmpl.h"
> +
> +#include "gotwebd.h"
> +
> +int gw_base(struct template *, const char *);
> +int gw_commits(struct template *);
> +int gw_navs(struct template *);
> +
> +static inline const char *
> +action_name(int action)
> +{
> + switch (action) {
> + case BLAME:
> + return"blame";
> + case BRIEFS:
> + return"briefs";
> + case COMMITS:
> + return"commits";
> + case DIFF:
> + return"diff";
> + case SUMMARY:
> + return"summary";
> + case TAG:
> + return"tag";
> + case TAGS:
> + return"tags";
> + case TREE:
> + return"tree";
> + default:
> + return "unknown";
> + }
> +}
> +
> +!}
> +
> +{{ define gw_base(struct template *tp, const char *title) }}
> +{!
> + struct request *c = tp->tp_arg;
> + struct server *srv = c->srv;
> + struct querystring *qs = c->t->qs;
> + const char *prfx = c->script_name;
> + const char *css = srv->custom_css;
> + char index[32];
> + int r;
> +
> + r = snprintf(index, sizeof(index), "%d", qs->index_page);
> + if (r < 0 || (size_t)r >= sizeof(index))
> + return -1;
> +!}
> +<!doctype html>
> +<html>
> + <head>
> + <meta charset="utf-8" />
> + <title>{{ title }}</title>
> + <meta name="viewport" content="initial-scale=.75" />
> + <meta name="msapplication-TileColor" content="#da532c" />
> + <meta name="theme-color" content="#ffffff"/>
> + <link rel="apple-touch-icon" sizes="180x180" href="{{ prfx }}apple-touch-icon.png" />
> + <link rel="icon" type="image/png" sizes="32x32" href="{{ prfx }}favicon-32x32.png" />
> + <link rel="icon" type="image/png" sizes="16x16" href="{{ prfx }}favicon-16x16.png" />
> + <link rel="manifest" href="{{ prfx }}site.webmanifest"/>
> + <link rel="mask-icon" href="{{ prfx }}safari-pinned-tab.svg" />
> + <link rel="stylesheet" type="text/css" href="{{ prfx }}{{ css }}" />
> + </head>
> + <body>
> + <div id="gw_body">
> + <div id="header">
> + <div id="got_link">
> + <a href="{{ srv->logo_url }}" target="_blank">
> + <imsg src="{{ prfx }}{{ srv->logo }}"
> + </a>
> + </div>
> + </div>
> + <div id="site_path">
> + <div id="site_link">
> + <a href="?index_page={{ index }}">{{ srv->site_link }}</a>
> + {{ if qs->path }}
> + {! /* ... */ !}
> + {{ end }}
> + {{ if qs->action != INDEX }}
> + {{ " / " }} {{ action_name(qs->action) }}
> + {{ end }}
> + </div>
> + </div>
> + <div id="content">
> + {{ render tp->tp_body }}
> + </div>
> + </div>
> + </body>
> +</html>
> +{{ end }}
> +
> +{{ define gw_commits(struct template *tp) }}
> +{!
> + const struct got_error *error = NULL;
> + struct repo_commit *rc;
> + struct request *c = tp->tp_arg;
> + struct server *srv = c->srv;
> + struct transport *t = c->t;
> +
> + error = got_get_repo_commits(c, srv->max_commits_display);
> + if (error)
> + return -1;
> +!}
> +<div class="commits_title_wrapper"
> + <div class="commits_title">Commits</div>
> +</div>
> +<div class="commits_content">
> + {{ tailq-foreach rc &t->repo_commits entry }}
> + <div class="commits_header_wrapper">
> + <div class="commits_header">
> + <div class="header_commit_title">Commit:</div>
> + <div class="header_commit">{{ rc->commit_id }}</div>
> + <div class="header_author_title">Author:</div>
> + <div class="header_author">{{ rc->author }}</div>
> + <div class="header_age_title">Date:</div>
> + <div class="header_age">...</div>
> + </div>
> + </div>
> + <div class="dotted_line"></div>
> + <div class="commit">
> + {{ rc->commit_msg }}
> + </div>
> + <div class="navs_wrapper">
> + <div class="navs">
> + {! /* previous link */ !}
> + {! /* next link */ !}
> + </div>
> + </div>
> + <div class="dotted_line"></div>
> + {{ end }}
> + {{ if t->next_id || t->prev_id }}
> + {{ render gw_navs(tp) }}
> + {{ end }}
> +</div>
> +{{ end }}
> +
> +{{ define gw_navs(struct template *tp) }}
> +<div id="np_wrapper">
> + <div id="nav_prev">
> + {! /* ... */ !}
> + </div>
> + <div id="nav_next">
> + {! /* ... */ !}
> + </div>
> +</div>
> +{{ end }}
> +
> +{!
> +
> +/*
> + * Example usage:
> + *
> + * Initialize the template:
> + *
> + * c->tp = template(c, puts_like_fns, putc_like_fns);
> + * if (c->tp == NULL)
> + * return got_error_from_errno("template");
> + *
> + * The call a "block" defined with ``{{ define ... }}'' as a normal C
> + * function:
> + *
> + * if (gw_base(c->tp, "page title") == -1)
> + * // error
> + */
> +
> +!}
> blob - /dev/null
> file + gotwebd/template/Makefile
> --- /dev/null
> +++ gotwebd/template/Makefile
> @@ -0,0 +1,21 @@
> +PROG = template
> +SRCS = template.c parse.y
> +
> +# XXX
> +NOMAN = Yes
> +
> +CFLAGS += -I${.CURDIR}
> +
> +WARNINGS = yes
> +
> +CDIAGFLAGS = -Wall -Wextra -Wpointer-arith -Wuninitialized
> +CDIAGFLAGS+= -Wstrict-prototypes -Wmissing-prototypes -Wunused
> +CDIAGFLAGS+= -Wsign-compare -Wshadow -Wno-unused-parameter
> +CDIAGFLAGS+= -Wno-missing-field-initializers
> +CDIAGFLAGS+= -Werror
> +
> +.if make(regress) || make(clean)
> +SUBDIR = regress
> +.endif
> +
> +.include <bsd.prog.mk>
> blob - /dev/null
> file + gotwebd/template/parse.y
> --- /dev/null
> +++ gotwebd/template/parse.y
> @@ -0,0 +1,704 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + * Copyright (c) 2007-2016 Reyk Floeter <reyk@openbsd.org>
> + * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
> + * Copyright (c) 2004 Ryan McBride <mcbride@openbsd.org>
> + * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
> + * Copyright (c) 2001 Markus Friedl. All rights reserved.
> + * Copyright (c) 2001 Daniel Hartmeier. All rights reserved.
> + * Copyright (c) 2001 Theo de Raadt. All rights reserved.
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +%{
> +
> +#include <sys/queue.h>
> +
> +#include <ctype.h>
> +#include <err.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <stdarg.h>
> +#include <stdint.h>
> +#include <string.h>
> +#include <unistd.h>
> +
> +#ifndef nitems
> +#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
> +#endif
> +
> +TAILQ_HEAD(files, file) files = TAILQ_HEAD_INITIALIZER(files);
> +static struct file {
> + TAILQ_ENTRY(file) entry;
> + FILE *stream;
> + char *name;
> + size_t ungetpos;
> + size_t ungetsize;
> + u_char *ungetbuf;
> + int eof_reached;
> + int lineno;
> + int errors;
> +} *file, *topfile;
> +int parse(const char *);
> +struct file *pushfile(const char *, int);
> +int popfile(void);
> +int yyparse(void);
> +int yylex(void);
> +int yyerror(const char *, ...)
> + __attribute__((__format__ (printf, 1, 2)))
> + __attribute__((__nonnull__ (1)));
> +int kw_cmp(const void *, const void *);
> +int lookup(char *);
> +int igetc(void);
> +int lgetc(int);
> +void lungetc(int);
> +int findeol(void);
> +
> +void dbg(void);
> +void printq(const char *);
> +
> +extern int nodebug;
> +
> +static int block;
> +static int in_define;
> +static int errors;
> +static char lerr[32];
> +
> +typedef struct {
> + union {
> + char *string;
> + } v;
> + int lineno;
> +} YYSTYPE;
> +
> +%}
> +
> +%token DEFINE ELSE END ERROR ESCAPE FINALLY IF INCLUDE
> +%token RENDER TQFOREACH UNSAFE URLESCAPE
> +%token <v.string> STRING
> +%type <v.string> string
> +%type <v.string> stringy
> +
> +%%
> +
> +grammar : /* empty */
> + | grammar include
> + | grammar verbatim
> + | grammar block
> + | grammar error { file->errors++; }
> + ;
> +
> +include : INCLUDE STRING {
> + struct file *nfile;
> +
> + if ((nfile = pushfile($2, 0)) == NULL) {
> + yyerror("failed to include file %s", $2);
> + free($2);
> + YYERROR;
> + }
> + free($2);
> +
> + file = nfile;
> + lungetc('\n');
> + }
> + ;
> +
> +verbatim : '!' verbatim1 '!' {
> + if (in_define) {
> + /* TODO: check template status and exit in case */
> + }
> + }
> + ;
> +
> +verbatim1 : /* empty */
> + | verbatim1 STRING {
> + if (*$2 != '\0') {
> + dbg();
> + puts($2);
> + }
> + free($2);
> + }
> + ;
> +
> +verbatims : /* empty */
> + | verbatims verbatim
> + ;
> +
> +raw : STRING {
> + dbg();
> + printf("if (tp->tp_puts(tp, ");
> + printq($1);
> + printf(") == -1) goto %s;\n", lerr);
> +
> + free($1);
> + }
> + ;
> +
> +block : define body end {
> + printf("%s:\n", lerr);
> + puts("return tp->tp_ret;");
> + puts("}");
> + in_define = 0;
> + }
> + | define body finally end {
> + puts("return tp->tp_ret;");
> + puts("}");
> + in_define = 0;
> + }
> + ;
> +
> +define : '{' DEFINE string '}' {
> + in_define = 1;
> + (void)snprintf(lerr, sizeof(lerr), "err%llu",
> + (unsigned long long)arc4random());
> +
> + dbg();
> + printf("int\n%s\n{\n", $3);
> +
> + free($3);
> + }
> + ;
> +
> +body : /* empty */
> + | body verbatim
> + | body raw
> + | body special
> + ;
> +
> +special : '{' RENDER string '}' {
> + dbg();
> + if (strrchr($3, ')') != NULL)
> + printf("if (%s == -1) goto %s;\n",
> + $3, lerr);
> + else
> + printf("if (%s != NULL && %s(tp) == -1) "
> + "goto %s;\n", $3, $3, lerr);
> + free($3);
> + }
> + | if body endif { puts("}"); }
> + | loop
> + | '{' string '|' ESCAPE '}' {
> + dbg();
> + printf("if (tp->tp_escape(tp, %s) == -1) goto %s;\n",
> + $2, lerr);
> + free($2);
> + }
> + | '{' string '|' UNSAFE '}' {
> + dbg();
> + printf("if (tp->tp_puts(tp, %s) == -1) goto %s;\n",
> + $2, lerr);
> + free($2);
> + }
> + | '{' string '|' URLESCAPE '}' {
> + dbg();
> + printf("if (tp_urlescape(tp, %s) == -1) goto %s;\n",
> + $2, lerr);
> + free($2);
> + }
> + | '{' string '}' {
> + dbg();
> + printf("if (tp->tp_escape(tp, %s) == -1) goto %s;\n",
> + $2, lerr);
> + free($2);
> + }
> + ;
> +
> +if : '{' IF stringy '}' {
> + dbg();
> + printf("if (%s) {\n", $3);
> + free($3);
> + }
> + ;
> +
> +endif : end
> + | else body end
> + | elsif body endif
> + ;
> +
> +elsif : '{' ELSE IF string '}' {
> + dbg();
> + printf("} else if (%s) {\n", $4);
> + free($4);
> + }
> + ;
> +
> +else : '{' ELSE '}' {
> + dbg();
> + puts("} else {");
> + }
> + ;
> +
> +loop : '{' TQFOREACH STRING STRING STRING '}' {
> + printf("TAILQ_FOREACH(%s, %s, %s) {\n",
> + $3, $4, $5);
> + free($3);
> + free($4);
> + free($5);
> + } body end {
> + puts("}");
> + }
> + ;
> +
> +end : '{' END '}'
> + ;
> +
> +finally : '{' FINALLY '}' {
> + dbg();
> + printf("%s:\n", lerr);
> + } verbatims
> + ;
> +
> +string : STRING string {
> + if (asprintf(&$$, "%s %s", $1, $2) == -1)
> + err(1, "asprintf");
> + free($1);
> + free($2);
> + }
> + | STRING
> + ;
> +
> +stringy : STRING
> + | STRING stringy {
> + if (asprintf(&$$, "%s %s", $1, $2) == -1)
> + err(1, "asprintf");
> + free($1);
> + free($2);
> + }
> + | '|' stringy {
> + if (asprintf(&$$, "|%s", $2) == -1)
> + err(1, "asprintf");
> + free($2);
> + }
> + ;
> +
> +%%
> +
> +struct keywords {
> + const char *k_name;
> + int k_val;
> +};
> +
> +int
> +yyerror(const char *fmt, ...)
> +{
> + va_list ap;
> + char *msg;
> +
> + file->errors++;
> + va_start(ap, fmt);
> + if (vasprintf(&msg, fmt, ap) == -1)
> + err(1, "yyerror vasprintf");
> + va_end(ap);
> + fprintf(stderr, "%s:%d: %s\n", file->name, yylval.lineno, msg);
> + free(msg);
> + return (0);
> +}
> +
> +int
> +kw_cmp(const void *k, const void *e)
> +{
> + return (strcmp(k, ((const struct keywords *)e)->k_name));
> +}
> +
> +int
> +lookup(char *s)
> +{
> + /* this has to be sorted always */
> + static const struct keywords keywords[] = {
> + { "define", DEFINE },
> + { "else", ELSE },
> + { "end", END },
> + { "escape", ESCAPE },
> + { "finally", FINALLY },
> + { "if", IF },
> + { "include", INCLUDE },
> + { "render", RENDER },
> + { "tailq-foreach", TQFOREACH },
> + { "unsafe", UNSAFE },
> + { "urlescape", URLESCAPE },
> + };
> + const struct keywords *p;
> +
> + p = bsearch(s, keywords, nitems(keywords), sizeof(keywords[0]),
> + kw_cmp);
> +
> + if (p)
> + return (p->k_val);
> + else
> + return (STRING);
> +}
> +
> +#define START_EXPAND 1
> +#define DONE_EXPAND 2
> +
> +static int expanding;
> +
> +int
> +igetc(void)
> +{
> + int c;
> +
> + while (1) {
> + if (file->ungetpos > 0)
> + c = file->ungetbuf[--file->ungetpos];
> + else
> + c = getc(file->stream);
> +
> + if (c == START_EXPAND)
> + expanding = 1;
> + else if (c == DONE_EXPAND)
> + expanding = 0;
> + else
> + break;
> + }
> + return (c);
> +}
> +
> +int
> +lgetc(int quotec)
> +{
> + int c, next;
> +
> + if (quotec) {
> + if ((c = igetc()) == EOF) {
> + yyerror("reached end of filewhile parsing "
> + "quoted string");
> + if (file == topfile || popfile() == EOF)
> + return (EOF);
> + return (quotec);
> + }
> + return (c);
> + }
> +
> + while ((c = igetc()) == '\\') {
> + next = igetc();
> + if (next != '\n') {
> + c = next;
> + break;
> + }
> + yylval.lineno = file->lineno;
> + file->lineno++;
> + }
> + if (c == '\t' || c == ' ') {
> + /* Compress blanks to a sigle space. */
> + do {
> + c = getc(file->stream);
> + } while (c == '\t' || c == ' ');
> + ungetc(c, file->stream);
> + c = ' ';
> + }
> +
> + if (c == EOF) {
> + /*
> + * Fake EOL when hit EOF for the first time. This gets line
> + * count rigchtif last line included file is syntactically
> + * invalid and has no newline.
> + */
> + if (file->eof_reached == 0) {
> + file->eof_reached = 1;
> + return ('\n');
> + }
> + while (c == EOF) {
> + if (file == topfile || popfile() == EOF)
> + return (EOF);
> + c = igetc();
> + }
> + }
> + return (c);
> +}
> +
> +void
> +lungetc(int c)
> +{
> + if (c == EOF)
> + return;
> +
> + if (file->ungetpos >= file->ungetsize) {
> + void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
> + if (p == NULL)
> + err(1, "reallocarray");
> + file->ungetbuf = p;
> + file->ungetsize *= 2;
> + }
> + file->ungetbuf[file->ungetpos++] = c;
> +}
> +
> +int
> +findeol(void)
> +{
> + int c;
> +
> + /* skip to either EOF or the first real EOL */
> + while (1) {
> + c = lgetc(0);
> + if (c == '\n') {
> + file->lineno++;
> + break;
> + }
> + if (c == EOF)
> + break;
> + }
> + return (ERROR);
> +}
> +
> +int
> +yylex(void)
> +{
> + char buf[8096];
> + char *p = buf;
> + int c;
> + int token;
> + int starting = 0;
> + int ending = 0;
> +
> + if (!in_define && block == 0) {
> + while ((c = lgetc(0)) != '{' && c != EOF) {
> + if (c == '\n')
> + file->lineno++;
> + }
> +
> + if (c == EOF)
> + return (0);
> +
> +newblock:
> + c = lgetc(0);
> + if (c == '{' || c == '!') {
> + if (c == '{')
> + block = '}';
> + else
> + block = c;
> + return (c);
> + }
> + if (c == '\n')
> + file->lineno++;
> + }
> +
> + while ((c = lgetc(0)) == ' ' || c == '\t' || c == '\n') {
> + if (c == '\n')
> + file->lineno++;
> + }
> +
> + if (c == EOF) {
> + yyerror("unterminated block");
> + return (0);
> + }
> +
> + yylval.lineno = file->lineno;
> +
> + if (block != 0 && c == block) {
> + if ((c = lgetc(0)) == '}') {
> + if (block == '!') {
> + block = 0;
> + return ('!');
> + }
> + block = 0;
> + return ('}');
> + }
> + lungetc(c);
> + c = block;
> + }
> +
> + if (in_define && block == 0) {
> + if (c == '{')
> + goto newblock;
> +
> + do {
> + if (starting) {
> + if (c == '!' || c == '{') {
> + lungetc('{');
> + lungetc(c);
> + break;
> + }
> + starting = 0;
> + lungetc(c);
> + c = '{';
> + } else if (c == '{') {
> + starting = 1;
> + continue;
> + }
> +
> + *p++ = c;
> + if ((size_t)(p - buf) >= sizeof(buf)) {
> + yyerror("string too long");
> + return (findeol());
> + }
> + } while ((c = lgetc(0)) != EOF && c != '\n');
> + *p = '\0';
> + if (c == EOF) {
> + yyerror("unterminated block");
> + return (0);
> + }
> + if (c == '\n')
> + file->lineno++;
> + if ((yylval.v.string = strdup(buf)) == NULL)
> + err(1, "strdup");
> + return (STRING);
> + }
> +
> + if (block == '!') {
> + do {
> + if (ending) {
> + if (c == '}') {
> + lungetc(c);
> + lungetc(block);
> + break;
> + }
> + ending = 0;
> + lungetc(c);
> + c = block;
> + } else if (c == '!') {
> + ending = 1;
> + continue;
> + }
> +
> + *p++ = c;
> + if ((size_t)(p - buf) >= sizeof(buf)) {
> + yyerror("line too long");
> + return (findeol());
> + }
> + } while ((c = lgetc(0)) != EOF && c != '\n');
> + *p = '\0';
> +
> + if (c == EOF) {
> + yyerror("unterminated block");
> + return (0);
> + }
> + if (c == '\n')
> + file->lineno++;
> +
> + if ((yylval.v.string = strdup(buf)) == NULL)
> + err(1, "strdup");
> + return (STRING);
> + }
> +
> + if (c == '|')
> + return (c);
> +
> + do {
> + if (c == '|') {
> + lungetc(c);
> + break;
> + }
> +
> + if (ending) {
> + if (c == '}') {
> + lungetc(c);
> + lungetc('}');
> + break;
> + }
> + ending = 0;
> + lungetc(c);
> + c = block;
> + } else if (c == '}') {
> + ending = 1;
> + continue;
> + }
> +
> + *p++ = c;
> + if ((size_t)(p - buf) >= sizeof(buf)) {
> + yyerror("string too long");
> + return (findeol());
> + }
> + } while ((c = lgetc(0)) != EOF && !isspace((unsigned char)c));
> + *p = '\0';
> +
> + if (c == EOF) {
> + yyerror("unterminated block");
> + return (0);
> + }
> + if (c == '\n')
> + file->lineno++;
> + if ((token = lookup(buf)) == STRING)
> + if ((yylval.v.string = strdup(buf)) == NULL)
> + err(1, "strdup");
> + return (token);
> +}
> +
> +struct file *
> +pushfile(const char *name, int secret)
> +{
> + struct file *nfile;
> +
> + if ((nfile = calloc(1, sizeof(*nfile))) == NULL)
> + err(1, "calloc");
> + if ((nfile->name = strdup(name)) == NULL)
> + err(1, "strdup");
> + if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
> + warn("can't open %s", nfile->name);
> + free(nfile->name);
> + free(nfile);
> + return (NULL);
> + }
> + nfile->lineno = TAILQ_EMPTY(&files) ? 1 : 0;
> + nfile->ungetsize = 16;
> + nfile->ungetbuf = malloc(nfile->ungetsize);
> + if (nfile->ungetbuf == NULL)
> + err(1, "malloc");
> + TAILQ_INSERT_TAIL(&files, nfile, entry);
> + return (nfile);
> +}
> +
> +int
> +popfile(void)
> +{
> + struct file *prev;
> +
> + if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
> + prev->errors += file->errors;
> +
> + TAILQ_REMOVE(&files, file, entry);
> + fclose(file->stream);
> + free(file->name);
> + free(file->ungetbuf);
> + free(file);
> + file = prev;
> + return (file ? 0 : EOF);
> +}
> +
> +int
> +parse(const char *filename)
> +{
> + if ((file = pushfile(filename, 0)) == 0)
> + return (-1);
> + topfile = file;
> +
> + yyparse();
> + errors = file->errors;
> + popfile();
> +
> + return (errors ? -1 : 0);
> +}
> +
> +void
> +dbg(void)
> +{
> + if (nodebug)
> + return;
> +
> + printf("#line %d ", yylval.lineno);
> + printq(file->name);
> + putchar('\n');
> +}
> +
> +void
> +printq(const char *str)
> +{
> + putchar('"');
> + for (; *str; ++str) {
> + if (*str == '"')
> + putchar('\\');
> + putchar(*str);
> + }
> + putchar('"');
> +}
> blob - /dev/null
> file + gotwebd/template/regress/00-empty.tmpl
> blob - /dev/null
> file + gotwebd/template/regress/01-noise-only.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/01-noise-only.tmpl
> @@ -0,0 +1,2 @@
> +only
> +noise
> blob - /dev/null
> file + gotwebd/template/regress/02-only-verbatim.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/02-only-verbatim.tmpl
> @@ -0,0 +1,13 @@
> +{! #include <stdio.h> !}
> +
> +noise
> +here
> +
> +{!
> +int
> +main(void)
> +{
> + puts("hello, world!");
> + return 0;
> +}
> +!}
> blob - /dev/null
> file + gotwebd/template/regress/02.expected
> --- /dev/null
> +++ gotwebd/template/regress/02.expected
> @@ -0,0 +1 @@
> +hello, world!
> blob - /dev/null
> file + gotwebd/template/regress/03-block.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/03-block.tmpl
> @@ -0,0 +1,17 @@
> +{! #include <stdlib.h> !}
> +
> +{{ define base(struct template *tp, const char *title) }}
> +{! char *foo = NULL; !}
> +<!doctype html>
> +<html>
> + <head>
> + <title>{{ title }}</title>
> + </head>
> + <body>
> + <h1>{{ title }}</h1>
> + {{ render tp->tp_body }}
> + </body>
> +</html>
> +{{ finally }}
> +{! free(foo); !}
> +{{ end }}
> blob - /dev/null
> file + gotwebd/template/regress/03.expected
> --- /dev/null
> +++ gotwebd/template/regress/03.expected
> @@ -0,0 +1,2 @@
> +<!doctype html><html><head><title> *hello* </title></head><body><h1> *hello* </h1></body></html>
> +<!doctype html><html><head><title><hello></title></head><body><h1><hello></h1></body></html>
> blob - /dev/null
> file + gotwebd/template/regress/04-flow.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/04-flow.tmpl
> @@ -0,0 +1,30 @@
> +{!
> +#include <stdlib.h>
> +#include <string.h>
> +!}
> +
> +{{ define base(struct template *tp, const char *title) }}
> +{! char *foo = NULL; !}
> +<!doctype html>
> +<html>
> + <head>
> + <title>{{ title }}</title>
> + </head>
> + <body>
> + <h1>{{ title }}</h1>
> + {{ if strchr(title, '*') != NULL }}
> + <p>"{{ title }}" has a '*' in it</p>
> + {{ if 1 }}
> + <p>tautology!</p>
> + {{ end }}
> + {{ else if strchr(title, '=') != NULL }}
> + <p>"{{ title }}" has a '=' in it!</p>
> + {{ else }}
> + <p>"{{ title }}" doesn't have a '*' in it</p>
> + {{ end }}
> + {{ render tp->tp_body }}
> + </body>
> +</html>
> +{{ finally }}
> +{! free(foo); !}
> +{{ end }}
> blob - /dev/null
> file + gotwebd/template/regress/04.expected
> --- /dev/null
> +++ gotwebd/template/regress/04.expected
> @@ -0,0 +1,2 @@
> +<!doctype html><html><head><title> *hello* </title></head><body><h1> *hello* </h1><p>" *hello* " has a '*' in it</p><p>tautology!</p></body></html>
> +<!doctype html><html><head><title><hello></title></head><body><h1><hello></h1><p>"<hello>" doesn't have a '*' in it</p></body></html>
> blob - /dev/null
> file + gotwebd/template/regress/05-loop.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/05-loop.tmpl
> @@ -0,0 +1,31 @@
> +{!
> +#include <sys/queue.h>
> +#include <string.h>
> +#include "lists.h"
> +
> +int list(struct template *, struct tailhead *);
> +
> +!}
> +
> +{{ define base(struct template *tp, struct tailhead *head) }}
> +<!doctype html>
> +<html>
> + <body>
> + {{ render list(tp, head) }}
> + </body>
> +</html>
> +{{ end }}
> +
> +{{ define list(struct template *tp, struct tailhead *head) }}
> + {! struct entry *np; !}
> + {{ if !TAILQ_EMPTY(head) }}
> + <p>items:</p>
> + <ul>
> + {{ tailq-foreach np head entries }}
> + <li>{{ np->text }}</li>
> + {{ end }}
> + </ul>
> + {{ else }}
> + <p>no items</p>
> + {{ end }}
> +{{ end }}
> blob - /dev/null
> file + gotwebd/template/regress/05.expected
> --- /dev/null
> +++ gotwebd/template/regress/05.expected
> @@ -0,0 +1,2 @@
> +<!doctype html><html><body><p>items:</p><ul><li>1</li><li>2</li></ul></body></html>
> +<!doctype html><html><body><p>no items</p></body></html>
> blob - /dev/null
> file + gotwebd/template/regress/06-escape.tmpl
> --- /dev/null
> +++ gotwebd/template/regress/06-escape.tmpl
> @@ -0,0 +1,14 @@
> +{! #include <stdlib.h> !}
> +
> +{{ define base(struct template *tp, const char *title) }}
> +<!doctype html>
> +<html>
> + <head>
> + <title>{{ title | urlescape }}</title>
> + </head>
> + <body>
> + <h1>{{ title | unsafe }}</h1>
> + {{ render tp->tp_body }}
> + </body>
> +</html>
> +{{ end }}
> blob - /dev/null
> file + gotwebd/template/regress/06.expected
> --- /dev/null
> +++ gotwebd/template/regress/06.expected
> @@ -0,0 +1,2 @@
> +<!doctype html><html><head><title>%20*hello*%20</title></head><body><h1> *hello* </h1></body></html>
> +<!doctype html><html><head><title><hello></title></head><body><h1><hello></h1></body></html>
> blob - /dev/null
> file + gotwebd/template/regress/Makefile
> --- /dev/null
> +++ gotwebd/template/regress/Makefile
> @@ -0,0 +1,55 @@
> +REGRESS_TARGETS = 00-empty \
> + 01-noise-only \
> + 02-only-verbatim \
> + 03-block \
> + 04-flow \
> + 05-loop \
> + 06-escape
> +
> +REGRESS_SETUP_ONCE = setup-comp
> +REGRESS_CLEANUP = clean-comp
> +NO_OBJ = Yes
> +
> +CFLAGS += -I${.CURDIR}/../
> +
> +setup-comp:
> + cp ${.CURDIR}/../tmpl.c .
> + ln -f ${.CURDIR}/../template template || \
> + ln -f ${.CURDIR}/../obj/template template
> +
> +clean-comp:
> + rm template
> + rm -f t got 0*.[cdo] runbase.[do] runlist.[do] tmpl.*
> +
> +.SUFFIXES: .tmpl .c .o
> +
> +.tmpl.c:
> + ./template $? > $@
> +
> +00-empty:
> + ./template 00-empty.tmpl >/dev/null
> +
> +01-noise-only:
> + ./template 01-noise-only.tmpl >/dev/null
> +
> +02-only-verbatim: 02-only-verbatim.o tmpl.o
> + ${CC} 02-only-verbatim.o tmpl.o -o t && ./t > got
> + diff -u ${.CURDIR}/02.expected got
> +
> +03-block: 03-block.o runbase.o tmpl.o
> + ${CC} 03-block.o runbase.o tmpl.o -o t && ./t > got
> + diff -u ${.CURDIR}/03.expected got
> +
> +04-flow: 04-flow.o runbase.o tmpl.o
> + ${CC} 04-flow.o runbase.o tmpl.o -o t && ./t > got
> + diff -u ${.CURDIR}/04.expected got
> +
> +05-loop: 05-loop.o runlist.o tmpl.o
> + ${CC} 05-loop.o runlist.o tmpl.o -o t && ./t > got
> + diff -u ${.CURDIR}/05.expected got
> +
> +06-escape: 06-escape.o runbase.o tmpl.o
> + ${CC} 06-escape.o runbase.o tmpl.o -o t && ./t > got
> + diff -u ${.CURDIR}/06.expected got
> +
> +.include <bsd.regress.mk>
> blob - /dev/null
> file + gotwebd/template/regress/lists.h
> --- /dev/null
> +++ gotwebd/template/regress/lists.h
> @@ -0,0 +1,7 @@
> +#include <sys/queue.h>
> +
> +TAILQ_HEAD(tailhead, entry);
> +struct entry {
> + char *text;
> + TAILQ_ENTRY(entry) entries;
> +};
> blob - /dev/null
> file + gotwebd/template/regress/runbase.c
> --- /dev/null
> +++ gotwebd/template/regress/runbase.c
> @@ -0,0 +1,69 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#include <err.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +
> +#include "tmpl.h"
> +
> +int base(struct template *, const char *title);
> +
> +int
> +my_putc(struct template *tp, int c)
> +{
> + FILE *fp = tp->tp_arg;
> +
> + if (putc(c, fp) < 0) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> +
> + return (0);
> +}
> +
> +int
> +my_puts(struct template *tp, const char *s)
> +{
> + FILE *fp = tp->tp_arg;
> +
> + if (fputs(s, fp) < 0) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> +
> + return (0);
> +}
> +
> +int
> +main(int argc, char **argv)
> +{
> + struct template *tp;
> +
> + if ((tp = template(stdout, my_puts, my_putc)) == NULL)
> + err(1, "template");
> +
> + base(tp, " *hello* ");
> + puts("");
> +
> + template_reset(tp);
> +
> + base(tp, "<hello>");
> + puts("");
> +
> + free(tp);
> + return (0);
> +}
> blob - /dev/null
> file + gotwebd/template/regress/runlist.c
> --- /dev/null
> +++ gotwebd/template/regress/runlist.c
> @@ -0,0 +1,89 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#include <err.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +
> +#include "tmpl.h"
> +#include "lists.h"
> +
> +int base(struct template *, struct tailhead *);
> +
> +int
> +my_putc(struct template *tp, int c)
> +{
> + FILE *fp = tp->tp_arg;
> +
> + if (putc(c, fp) < 0) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> +
> + return (0);
> +}
> +
> +int
> +my_puts(struct template *tp, const char *s)
> +{
> + FILE *fp = tp->tp_arg;
> +
> + if (fputs(s, fp) < 0) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> +
> + return (0);
> +}
> +
> +int
> +main(int argc, char **argv)
> +{
> + struct template *tp;
> + struct tailhead head;
> + struct entry *np;
> + int i;
> +
> + if ((tp = template(stdout, my_puts, my_putc)) == NULL)
> + err(1, "template");
> +
> + TAILQ_INIT(&head);
> + for (i = 0; i < 2; ++i) {
> + if ((np = calloc(1, sizeof(*np))) == NULL)
> + err(1, "calloc");
> + if (asprintf(&np->text, "%d", i+1) == -1)
> + err(1, "asprintf");
> + TAILQ_INSERT_TAIL(&head, np, entries);
> + }
> +
> + base(tp, &head);
> + puts("");
> +
> + while ((np = TAILQ_FIRST(&head))) {
> + TAILQ_REMOVE(&head, np, entries);
> + free(np->text);
> + free(np);
> + }
> +
> + template_reset(tp);
> +
> + base(tp, &head);
> + puts("");
> +
> + free(tp);
> +
> + return (0);
> +}
> blob - /dev/null
> file + gotwebd/template/template.c
> --- /dev/null
> +++ gotwebd/template/template.c
> @@ -0,0 +1,67 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#include <err.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <unistd.h>
> +
> +int parse(const char *);
> +
> +int nodebug;
> +
> +static void __dead
> +usage(void)
> +{
> + fprintf(stderr, "usage: %s [file...]\n",
> + getprogname());
> + exit(1);
> +}
> +
> +int
> +main(int argc, char **argv)
> +{
> + int ch, i;
> +
> + if (pledge("stdio rpath", NULL) == -1)
> + err(1, "pledge");
> +
> + while ((ch = getopt(argc, argv, "G")) != -1) {
> + switch (ch) {
> + case 'G':
> + nodebug = 1;
> + break;
> + default:
> + usage();
> + }
> + }
> + argc -= optind;
> + argv += optind;
> +
> + /* preamble */
> + puts("#include \"tmpl.h\"");
> +
> + if (argc == 0) {
> + parse("/dev/stdin");
> + exit(0);
> + }
> +
> + for (i = 0; i < argc; ++i)
> + if (parse(argv[i]) == -1)
> + return (1);
> +
> + return (0);
> +}
> blob - /dev/null
> file + gotwebd/template/tmpl.c
> --- /dev/null
> +++ gotwebd/template/tmpl.c
> @@ -0,0 +1,105 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#include <ctype.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +
> +#include "tmpl.h"
> +
> +int
> +tp_urlescape(struct template *tp, const char *str)
> +{
> + int r;
> + char tmp[4];
> +
> + for (; *str; ++str) {
> + if (iscntrl((unsigned char)*str) ||
> + isspace((unsigned char)*str) ||
> + *str == '\'' || *str == '"' || *str == '\\') {
> + r = snprintf(tmp, sizeof(tmp), "%%%2X", *str);
> + if (r < 0 || (size_t)r >= sizeof(tmp)) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> + if (tp->tp_puts(tp, tmp) == -1)
> + return (-1);
> + } else {
> + if (tp->tp_putc(tp, *str) == -1)
> + return (-1);
> + }
> + }
> +
> + return (0);
> +}
> +
> +int
> +tp_htmlescape(struct template *tp, const char *str)
> +{
> + int r;
> +
> + for (; *str; ++str) {
> + switch (*str) {
> + case '<':
> + r = tp->tp_puts(tp, "<");
> + break;
> + case '>':
> + r = tp->tp_puts(tp, ">");
> + break;
> + case '&':
> + r = tp->tp_puts(tp, "&");
> + break;
> + case '"':
> + r = tp->tp_puts(tp, """);
> + break;
> + case '\'':
> + r = tp->tp_puts(tp, "'");
> + break;
> + default:
> + r = tp->tp_putc(tp, *str);
> + break;
> + }
> +
> + if (r == -1) {
> + tp->tp_ret = -1;
> + return (-1);
> + }
> + }
> +
> + return (0);
> +}
> +
> +struct template *
> +template(void *arg, tmpl_puts putsfn, tmpl_putc putcfn)
> +{
> + struct template *tp;
> +
> + if ((tp = calloc(1, sizeof(*tp))) == NULL)
> + return (NULL);
> +
> + tp->tp_arg = arg;
> + tp->tp_escape = tp_htmlescape;
> + tp->tp_puts = putsfn;
> + tp->tp_putc = putcfn;
> +
> + return (tp);
> +}
> +
> +void
> +template_reset(struct template *tp)
> +{
> + tp->tp_ret = 0;
> +}
> blob - /dev/null
> file + gotwebd/template/tmpl.h
> --- /dev/null
> +++ gotwebd/template/tmpl.h
> @@ -0,0 +1,42 @@
> +/*
> + * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
> + *
> + * Permission to use, copy, modify, and distribute this software for any
> + * purpose with or without fee is hereby granted, provided that the above
> + * copyright notice and this permission notice appear in all copies.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
> + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> + */
> +
> +#ifndef TMPL_H
> +#define TMPL_H
> +
> +struct template;
> +
> +typedef int (*tmpl_puts)(struct template *, const char *);
> +typedef int (*tmpl_putc)(struct template *, int);
> +
> +struct template {
> + void *tp_arg;
> + tmpl_puts tp_escape;
> + tmpl_puts tp_puts;
> + tmpl_putc tp_putc;
> +
> + int tp_ret;
> +
> + int (*tp_body)(struct template *);
> +};
> +
> +int tp_urlescape(struct template *, const char *);
> +int tp_htmlescape(struct template *, const char *);
> +
> +struct template *template(void *, tmpl_puts, tmpl_putc);
> +void template_reset(struct template *);
> +
> +#endif
>
--
Tracey Emery
[RFC] template system for gotwebd