From: David Bremner <bremner@debian.org> The character set is chosen to be suitable for pathnames, and the same as that used by contrib/nmbug --- util/Makefile.local | 2 +- util/hex-escape.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++++ util/hex-escape.h | 15 +++++ 3 files changed, 166 insertions(+), 1 deletions(-) create mode 100644 util/hex-escape.c create mode 100644 util/hex-escape.h diff --git a/util/Makefile.local b/util/Makefile.local index 26e4c3f..2e63932 100644 --- a/util/Makefile.local +++ b/util/Makefile.local @@ -3,7 +3,7 @@ dir := util extra_cflags += -I$(srcdir)/$(dir) -libutil_c_srcs := $(dir)/xutil.c $(dir)/error_util.c +libutil_c_srcs := $(dir)/xutil.c $(dir)/error_util.c $(dir)/hex-escape.c libutil_modules := $(libutil_c_srcs:.c=.o) diff --git a/util/hex-escape.c b/util/hex-escape.c new file mode 100644 index 0000000..3e08465 --- /dev/null +++ b/util/hex-escape.c @@ -0,0 +1,150 @@ +/* pathname.c - Manage encoding and decoding of byte strings into path names + * + * Copyright (c) 2011 David Bremner + * + * 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/ . + * + * Author: David Bremner <david@tethera.net> + */ + +#include <string.h> +#include <talloc.h> +#include "error_util.h" +#include "hex-escape.h" + +static const size_t default_buf_size=1024; + +static const char* output_charset= + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-_@=.:,"; + +static const char escape_char='%'; + +static int +is_output (char c) { + return (strchr (output_charset, c) != NULL); +} + + +static int +maybe_realloc(void *ctx, size_t needed, char **out, size_t *out_size) +{ + if (*out_size < needed) { + + if (*out == NULL) + *out = talloc_size(ctx,needed); + else + *out = talloc_realloc(ctx,*out,char,needed); + + if (*out == NULL) + return 0; + + *out_size = needed; + } + return 1; +} + + +hex_status_t +hex_encode (void *ctx, const char *in, char **out, size_t *out_size) +{ + + const char *p; + char *q; + + int escape_count=0; + size_t needed; + + for (p = in; *p; p++) + escape_count += (! is_output (*p)); + + needed = strlen (in) + 2*escape_count + 1; + + if (*out == NULL) + *out_size=0; + + if (!maybe_realloc (ctx, needed, out, out_size)) + return HEX_OUT_OF_MEMORY; + + q = *out; + p = in; + + while (*p) { + if (is_output (*p)) { + *q++ = *p++; + } else { + sprintf (q, "%%%02x", *p++); + q += 3; + } + } + + *q = '\0'; + return HEX_SUCCESS; +} + + +hex_status_t +hex_decode (void *ctx, const char *in, char **out, size_t *out_size) { + + char buf[3]; + + const char *p; + char *q; + + size_t escape_count = 0; + size_t needed = 0; + + size_t len = strlen (in); + + for (p = in; *p; p++) + escape_count += (*p == escape_char); + + needed = len - escape_count*2 +1; + + if (!maybe_realloc(ctx, needed, out, out_size)) + return HEX_OUT_OF_MEMORY; + + p = in; + q = *out; + buf[2]=0; + + + while (*p) { + + if (*p == escape_char) { + + char *endp; + + if (len < 3) + return HEX_SYNTAX_ERROR; + + buf[0]=p[1]; + buf[1]=p[2]; + + *q = strtol(buf, &endp, 16); + + if (endp != buf+2) + return HEX_SYNTAX_ERROR; + + len -= 3; + p += 3; + q++; + } else { + *q++ = *p++; + } + } + + *q = '\0'; + + return HEX_SUCCESS; +} diff --git a/util/hex-escape.h b/util/hex-escape.h new file mode 100644 index 0000000..98ecbe0 --- /dev/null +++ b/util/hex-escape.h @@ -0,0 +1,15 @@ +#ifndef _HEX_ESCAPE_H +#define _HEX_ESCAPE_H + +typedef enum hex_status { + HEX_SUCCESS = 0, + HEX_SYNTAX_ERROR, + HEX_OUT_OF_MEMORY +} hex_status_t; + +hex_status_t +hex_encode (void *talloc_ctx, const char *in, char **out, size_t *out_size); + +hex_status_t +hex_decode (void *talloc_ctx, const char *in, char **out, size_t *out_size); +#endif -- 1.7.5.4