commit: 04393e863a70127807949915eb670267a813681d
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date: Sat, 18 Oct 2025 02:56:21 +0200
init
Diffstat:
8 files changed, 748 insertions(+), 0 deletions(-)
diff --git a/.clang-format b/.clang-format
@@ -0,0 +1,23 @@
+# SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
+AlignAfterOpenBracket: true
+AlignConsecutiveAssignments: false
+AlignOperands: true
+AlignTrailingComments: true
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: true
+AllowShortIfStatementsOnASingleLine: true
+AlwaysBreakAfterReturnType: AllDefinitions
+BinPackArguments: false
+BinPackParameters: false
+BreakBeforeBraces: Allman
+SpaceBeforeParens: Never
+IncludeBlocks: Regroup
+ReflowComments: false
+SortIncludes: true
+UseTab: ForIndentation
+IndentWidth: 2
+TabWidth: 2
+ColumnLimit: 100
+
+NamespaceIndentation: All
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1,3 @@
+# Copyright © 2025 Haelwenn (lanodan) Monnier <contact+cmd-cidr@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
+/cidr2list
+\ No newline at end of file
diff --git a/LICENSES/MPL-2.0.txt b/LICENSES/MPL-2.0.txt
@@ -0,0 +1,373 @@
+Mozilla Public License Version 2.0
+==================================
+
+1. Definitions
+--------------
+
+1.1. "Contributor"
+ means each individual or legal entity that creates, contributes to
+ the creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+ means the combination of the Contributions of others (if any) used
+ by a Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+ means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+ means Source Code Form to which the initial Contributor has attached
+ the notice in Exhibit A, the Executable Form of such Source Code
+ Form, and Modifications of such Source Code Form, in each case
+ including portions thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+ means
+
+ (a) that the initial Contributor has attached the notice described
+ in Exhibit B to the Covered Software; or
+
+ (b) that the Covered Software was made available under the terms of
+ version 1.1 or earlier of the License, but not also under the
+ terms of a Secondary License.
+
+1.6. "Executable Form"
+ means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+ means a work that combines Covered Software with other material, in
+ a separate file or files, that is not Covered Software.
+
+1.8. "License"
+ means this document.
+
+1.9. "Licensable"
+ means having the right to grant, to the maximum extent possible,
+ whether at the time of the initial grant or subsequently, any and
+ all of the rights conveyed by this License.
+
+1.10. "Modifications"
+ means any of the following:
+
+ (a) any file in Source Code Form that results from an addition to,
+ deletion from, or modification of the contents of Covered
+ Software; or
+
+ (b) any new file in Source Code Form that contains any Covered
+ Software.
+
+1.11. "Patent Claims" of a Contributor
+ means any patent claim(s), including without limitation, method,
+ process, and apparatus claims, in any patent Licensable by such
+ Contributor that would be infringed, but for the grant of the
+ License, by the making, using, selling, offering for sale, having
+ made, import, or transfer of either its Contributions or its
+ Contributor Version.
+
+1.12. "Secondary License"
+ means either the GNU General Public License, Version 2.0, the GNU
+ Lesser General Public License, Version 2.1, the GNU Affero General
+ Public License, Version 3.0, or any later versions of those
+ licenses.
+
+1.13. "Source Code Form"
+ means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+ means an individual or a legal entity exercising rights under this
+ License. For legal entities, "You" includes any entity that
+ controls, is controlled by, or is under common control with You. For
+ purposes of this definition, "control" means (a) the power, direct
+ or indirect, to cause the direction or management of such entity,
+ whether by contract or otherwise, or (b) ownership of more than
+ fifty percent (50%) of the outstanding shares or beneficial
+ ownership of such entity.
+
+2. License Grants and Conditions
+--------------------------------
+
+2.1. Grants
+
+Each Contributor hereby grants You a world-wide, royalty-free,
+non-exclusive license:
+
+(a) under intellectual property rights (other than patent or trademark)
+ Licensable by such Contributor to use, reproduce, make available,
+ modify, display, perform, distribute, and otherwise exploit its
+ Contributions, either on an unmodified basis, with Modifications, or
+ as part of a Larger Work; and
+
+(b) under Patent Claims of such Contributor to make, use, sell, offer
+ for sale, have made, import, and otherwise transfer either its
+ Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+The licenses granted in Section 2.1 with respect to any Contribution
+become effective for each Contribution on the date the Contributor first
+distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+The licenses granted in this Section 2 are the only rights granted under
+this License. No additional rights or licenses will be implied from the
+distribution or licensing of Covered Software under this License.
+Notwithstanding Section 2.1(b) above, no patent license is granted by a
+Contributor:
+
+(a) for any code that a Contributor has removed from Covered Software;
+ or
+
+(b) for infringements caused by: (i) Your and any other third party's
+ modifications of Covered Software, or (ii) the combination of its
+ Contributions with other software (except as part of its Contributor
+ Version); or
+
+(c) under Patent Claims infringed by Covered Software in the absence of
+ its Contributions.
+
+This License does not grant any rights in the trademarks, service marks,
+or logos of any Contributor (except as may be necessary to comply with
+the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+No Contributor makes additional grants as a result of Your choice to
+distribute the Covered Software under a subsequent version of this
+License (see Section 10.2) or under the terms of a Secondary License (if
+permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+Each Contributor represents that the Contributor believes its
+Contributions are its original creation(s) or it has sufficient rights
+to grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+This License is not intended to limit any rights You have under
+applicable copyright doctrines of fair use, fair dealing, or other
+equivalents.
+
+2.7. Conditions
+
+Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
+in Section 2.1.
+
+3. Responsibilities
+-------------------
+
+3.1. Distribution of Source Form
+
+All distribution of Covered Software in Source Code Form, including any
+Modifications that You create or to which You contribute, must be under
+the terms of this License. You must inform recipients that the Source
+Code Form of the Covered Software is governed by the terms of this
+License, and how they can obtain a copy of this License. You may not
+attempt to alter or restrict the recipients' rights in the Source Code
+Form.
+
+3.2. Distribution of Executable Form
+
+If You distribute Covered Software in Executable Form then:
+
+(a) such Covered Software must also be made available in Source Code
+ Form, as described in Section 3.1, and You must inform recipients of
+ the Executable Form how they can obtain a copy of such Source Code
+ Form by reasonable means in a timely manner, at a charge no more
+ than the cost of distribution to the recipient; and
+
+(b) You may distribute such Executable Form under the terms of this
+ License, or sublicense it under different terms, provided that the
+ license for the Executable Form does not attempt to limit or alter
+ the recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+You may create and distribute a Larger Work under terms of Your choice,
+provided that You also comply with the requirements of this License for
+the Covered Software. If the Larger Work is a combination of Covered
+Software with a work governed by one or more Secondary Licenses, and the
+Covered Software is not Incompatible With Secondary Licenses, this
+License permits You to additionally distribute such Covered Software
+under the terms of such Secondary License(s), so that the recipient of
+the Larger Work may, at their option, further distribute the Covered
+Software under the terms of either this License or such Secondary
+License(s).
+
+3.4. Notices
+
+You may not remove or alter the substance of any license notices
+(including copyright notices, patent notices, disclaimers of warranty,
+or limitations of liability) contained within the Source Code Form of
+the Covered Software, except that You may alter any license notices to
+the extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+You may choose to offer, and to charge a fee for, warranty, support,
+indemnity or liability obligations to one or more recipients of Covered
+Software. However, You may do so only on Your own behalf, and not on
+behalf of any Contributor. You must make it absolutely clear that any
+such warranty, support, indemnity, or liability obligation is offered by
+You alone, and You hereby agree to indemnify every Contributor for any
+liability incurred by such Contributor as a result of warranty, support,
+indemnity or liability terms You offer. You may include additional
+disclaimers of warranty and limitations of liability specific to any
+jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+---------------------------------------------------
+
+If it is impossible for You to comply with any of the terms of this
+License with respect to some or all of the Covered Software due to
+statute, judicial order, or regulation then You must: (a) comply with
+the terms of this License to the maximum extent possible; and (b)
+describe the limitations and the code they affect. Such description must
+be placed in a text file included with all distributions of the Covered
+Software under this License. Except to the extent prohibited by statute
+or regulation, such description must be sufficiently detailed for a
+recipient of ordinary skill to be able to understand it.
+
+5. Termination
+--------------
+
+5.1. The rights granted under this License will terminate automatically
+if You fail to comply with any of its terms. However, if You become
+compliant, then the rights granted under this License from a particular
+Contributor are reinstated (a) provisionally, unless and until such
+Contributor explicitly and finally terminates Your grants, and (b) on an
+ongoing basis, if such Contributor fails to notify You of the
+non-compliance by some reasonable means prior to 60 days after You have
+come back into compliance. Moreover, Your grants from a particular
+Contributor are reinstated on an ongoing basis if such Contributor
+notifies You of the non-compliance by some reasonable means, this is the
+first time You have received notice of non-compliance with this License
+from such Contributor, and You become compliant prior to 30 days after
+Your receipt of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+infringement claim (excluding declaratory judgment actions,
+counter-claims, and cross-claims) alleging that a Contributor Version
+directly or indirectly infringes any patent, then the rights granted to
+You by any and all Contributors for the Covered Software under Section
+2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all
+end user license agreements (excluding distributors and resellers) which
+have been validly granted by You or Your distributors under this License
+prior to termination shall survive termination.
+
+************************************************************************
+* *
+* 6. Disclaimer of Warranty *
+* ------------------------- *
+* *
+* Covered Software is provided under this License on an "as is" *
+* basis, without warranty of any kind, either expressed, implied, or *
+* statutory, including, without limitation, warranties that the *
+* Covered Software is free of defects, merchantable, fit for a *
+* particular purpose or non-infringing. The entire risk as to the *
+* quality and performance of the Covered Software is with You. *
+* Should any Covered Software prove defective in any respect, You *
+* (not any Contributor) assume the cost of any necessary servicing, *
+* repair, or correction. This disclaimer of warranty constitutes an *
+* essential part of this License. No use of any Covered Software is *
+* authorized under this License except under this disclaimer. *
+* *
+************************************************************************
+
+************************************************************************
+* *
+* 7. Limitation of Liability *
+* -------------------------- *
+* *
+* Under no circumstances and under no legal theory, whether tort *
+* (including negligence), contract, or otherwise, shall any *
+* Contributor, or anyone who distributes Covered Software as *
+* permitted above, be liable to You for any direct, indirect, *
+* special, incidental, or consequential damages of any character *
+* including, without limitation, damages for lost profits, loss of *
+* goodwill, work stoppage, computer failure or malfunction, or any *
+* and all other commercial damages or losses, even if such party *
+* shall have been informed of the possibility of such damages. This *
+* limitation of liability shall not apply to liability for death or *
+* personal injury resulting from such party's negligence to the *
+* extent applicable law prohibits such limitation. Some *
+* jurisdictions do not allow the exclusion or limitation of *
+* incidental or consequential damages, so this exclusion and *
+* limitation may not apply to You. *
+* *
+************************************************************************
+
+8. Litigation
+-------------
+
+Any litigation relating to this License may be brought only in the
+courts of a jurisdiction where the defendant maintains its principal
+place of business and such litigation shall be governed by laws of that
+jurisdiction, without reference to its conflict-of-law provisions.
+Nothing in this Section shall prevent a party's ability to bring
+cross-claims or counter-claims.
+
+9. Miscellaneous
+----------------
+
+This License represents the complete agreement concerning the subject
+matter hereof. If any provision of this License is held to be
+unenforceable, such provision shall be reformed only to the extent
+necessary to make it enforceable. Any law or regulation which provides
+that the language of a contract shall be construed against the drafter
+shall not be used to construe this License against a Contributor.
+
+10. Versions of the License
+---------------------------
+
+10.1. New Versions
+
+Mozilla Foundation is the license steward. Except as provided in Section
+10.3, no one other than the license steward has the right to modify or
+publish new versions of this License. Each version will be given a
+distinguishing version number.
+
+10.2. Effect of New Versions
+
+You may distribute the Covered Software under the terms of the version
+of the License under which You originally received the Covered Software,
+or under the terms of any subsequent version published by the license
+steward.
+
+10.3. Modified Versions
+
+If you create software not governed by this License, and you want to
+create a new license for such software, you may create and use a
+modified version of this License if you rename the license and remove
+any references to the name of the license steward (except to note that
+such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+Licenses
+
+If You choose to distribute Source Code Form that is Incompatible With
+Secondary Licenses under the terms of this version of the License, the
+notice described in Exhibit B of this License must be attached.
+
+Exhibit A - Source Code Form License Notice
+-------------------------------------------
+
+ This Source Code Form is subject to the terms of the Mozilla Public
+ License, v. 2.0. If a copy of the MPL was not distributed with this
+ file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular
+file, then You may include the notice in a location (such as a LICENSE
+file in a relevant directory) where a recipient would be likely to look
+for such a notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+---------------------------------------------------------
+
+ This Source Code Form is "Incompatible With Secondary Licenses", as
+ defined by the Mozilla Public License, v. 2.0.
diff --git a/Makefile b/Makefile
@@ -0,0 +1,14 @@
+# Copyright © 2025 Haelwenn (lanodan) Monnier <contact+cmd-cidr@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
+
+cidr2list: cidr2list.c
+ $(CC) -std=c99 $(CFLAGS) $(CPPFLAGS) -o cidr2list cidr2list.c $(LDFLAGS) $(LDSTATIC)
+
+.PHONY: clean
+clean:
+ rm cidr2list
+
+.PHONY: format
+format:
+ clang-format -style=file -assume-filename=.clang-format -i *.[ch]
+
diff --git a/authorized_keys.git b/authorized_keys.git
@@ -0,0 +1,5 @@
+# How to setup: git config gpg.ssh.allowedSignersFile authorized_keys.git
+contact@hacktivis.me ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKAxeQh6KJGg89yivTtmUtjxp80inHBrL5sMdt+Kg1ed haelwenn@NightmareMoon
+contact@hacktivis.me ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIC6LRxSNagh9NlEYLUqA8o/4HiUStEymeyvjFtNZeEIe haelwenn@cloudchaser
+# Copyright © 2025 Haelwenn (lanodan) Monnier <contact+cmd-cidr@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
diff --git a/cidr2list.c b/cidr2list.c
@@ -0,0 +1,152 @@
+// Copyright © 2025 Haelwenn (lanodan) Monnier <contact+cmd-cidr@hacktivis.me>
+// SPDX-License-Identifier: MPL-2.0
+
+#define _POSIX_C_SOURCE 202405L
+#include <ctype.h>
+#include <endian.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct inet4_cidr
+{
+ uint32_t addr;
+ uint8_t cidr;
+ uint32_t nmask;
+};
+
+bool
+str_inet4(const char *str, size_t size, struct inet4_cidr *res)
+{
+ uint8_t dot[4] = {0, 0, 0, 0};
+ uint8_t cidr = 32;
+
+ uint8_t di = 0;
+ for(size_t i = 0; i < size; i++)
+ {
+ if(str[i] == '.')
+ {
+ di++;
+ if(di == 4)
+ {
+ fprintf(
+ stderr, "cird2list: error: Invalid IPv4 address, found more than 4 dots: %s\n", str);
+ return false;
+ }
+ continue;
+ }
+
+ if(isdigit(str[i]))
+ {
+ dot[di] *= 10;
+ dot[di] += str[i] - '0';
+ continue;
+ }
+
+ if(i > 1 && str[i] == '/' && i + 1 < size && isdigit(str[i + 1]))
+ {
+ i++;
+ cidr = str[i] - '0';
+
+ if(i + 1 < size && isdigit(str[i + 1]))
+ {
+ i++;
+ cidr *= 10;
+ cidr += str[i] - '0';
+ }
+
+ if(cidr > 32)
+ {
+ fprintf(stderr, "cird2list: error: CIDR suffix (/%d) is higher than /32: %s\n", cidr, str);
+ return false;
+ }
+
+ break;
+ }
+
+ if(isspace(str[i])) continue;
+
+ fprintf(stderr, "cird2list: error: Invalid IPv4 address, found '%c' (0x%X)\n", str[i], str[i]);
+ return false;
+ }
+
+ if(di != 3)
+ {
+ fprintf(stderr, "cird2list: error: Invalid IPv4 address, found %d dots, expected 4\n", di + 1);
+ return false;
+ }
+
+#if 0
+ fprintf(stderr, "cird2list: DEBUG: %s -> %d.%d.%d.%d/%d\n", str, dot[0], dot[1], dot[2], dot[3], cidr);
+#endif
+
+ uint32_t nmask = 0xFFFFFFFFUL;
+ switch(cidr)
+ {
+ // Make sure to avoid overflow
+ case 0:
+ nmask = 0;
+ break;
+ // 2^(32-cidr) - 1
+ default:
+ nmask ^= (1 << (32 - cidr)) - 1;
+ }
+#if 0
+ fprintf(stderr, "cird2list: DEBUG: nmask (/%d): ", cidr);
+ fprintf(stderr, "%d.%d.%d.%d\n", (nmask >> 24) & 0xFF, (nmask >> 16) & 0xFF, (nmask >> 8) & 0xFF, (nmask) & 0xFF);
+#endif
+
+ res->addr = (dot[0] << 24) | (dot[1] << 16) | (dot[2] << 8) | dot[3];
+ res->cidr = cidr;
+ res->nmask = nmask;
+
+ return true;
+}
+
+int
+main(void)
+{
+ char *line = NULL;
+ size_t linelen = 0;
+
+ while(true)
+ {
+ errno = 0;
+ ssize_t nread = getline(&line, &linelen, stdin);
+ if(nread < 0)
+ {
+ if(errno == 0) break;
+
+ fprintf(stderr, "cird2list: error: Failed reading line: %s\n", strerror(errno));
+ return 1;
+ }
+
+ if(line[nread - 1] == '\n') line[--nread] = '\0';
+
+ struct inet4_cidr addr;
+ if(!str_inet4(line, (size_t)nread, &addr)) return 1;
+
+ uint32_t start = addr.addr & addr.nmask;
+#if 0
+ fprintf(stderr, "cird2list: DEBUG: start: ");
+ fprintf(stderr, "%d.%d.%d.%d\n", (start >> 24) & 0xFF, (start >> 16) & 0xFF, (start >> 8) & 0xFF, start & 0xFF);
+#endif
+
+ uint32_t end = start | (addr.nmask ^ 0xFFFFFFFFUL);
+#if 0
+ fprintf(stderr, "cird2list: DEBUG: end: ");
+ fprintf(stderr, "%d.%d.%d.%d\n", (end >> 24) & 0xFF, (end >> 16) & 0xFF, (end >> 8) & 0xFF, end & 0xFF);
+#endif
+
+ for(uint32_t ai = start; ai <= end; ai++)
+ {
+ printf("%d.%d.%d.%d\n", (ai >> 24) & 0xFF, (ai >> 16) & 0xFF, (ai >> 8) & 0xFF, ai & 0xFF);
+ }
+ }
+
+ free(line);
+ return 0;
+}
diff --git a/tap.sh b/tap.sh
@@ -0,0 +1,150 @@
+#!/bin/false
+# extracted from https://hacktivis.me/git/utils-std
+# SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
+
+count=0
+err=0
+
+# t [--exit=n] [--input=str] <test_name> <expected_output> <arguments ...>
+t() {
+ exp_ret=0
+ for i; do
+ case "$i" in
+ --exit=*)
+ exp_ret="${i#*=}"
+ shift
+ ;;
+ --input=*)
+ input="${i#*=}"
+ shift
+ ;;
+ --)
+ shift
+ break
+ ;;
+ # Note: * is still a wildcard, even with a range before
+ -[a-zA-Z0-9]|--[a-zA-Z0-9]*=*)
+ printf 'Unknown option: %s\n' "$i"
+ exit 2
+ ;;
+ *)
+ break
+ ;;
+ esac
+ done
+ name="$1"; shift
+ exp_out="$1"; shift
+
+ if [ "${input+set}" = "set" ]; then
+ # Append a final slash so sh(1) doesn't trims final newlines
+ out="$(printf "${input?}" | "${target?}" "$@" 2>&1;r=$?;printf %s /;exit $r)"
+ ret="$?"
+ else
+ # Append a final slash so sh(1) doesn't trims final newlines
+ out="$("${target?}" "$@" 2>&1;r=$?;printf %s /;exit $r)"
+ ret="$?"
+ fi
+
+ out="${out%/}"
+ count=$((count+1))
+
+ if [ "$ret" != "$exp_ret" ]; then
+ printf 'not ok %d - %s\n' "$count" "$name"
+ printf '# Expected exit code %d, got %d\n' "$exp_ret" "$ret"
+ printf '# == Got ==\n'
+ printf '# %s\n' "$out" | sed -e 's;^[^#];# ;'
+ err=1
+ elif [ "$out" != "$exp_out" ]; then
+ printf 'not ok %d - %s\n' "$count" "$name"
+ printf '# == Expected ==\n'
+ printf '# %s\n' "$exp_out" | sed -e 's;^[^#];# ;'
+ printf '# == Got ==\n'
+ printf '# %s\n' "$out" | sed -e 's;^[^#];# ;'
+ err=1
+ else
+ printf 'ok %d - %s\n' "$count" "$name"
+ fi
+}
+
+# t_cmd [--exit=n] <test_name> <expected_output> <command> [arguments]
+t_cmd() {
+ exp_ret=0
+ for i; do
+ case "$i" in
+ --exit=*)
+ exp_ret="${i#*=}"
+ shift
+ ;;
+ --)
+ shift
+ break
+ ;;
+ # Note: * is still a wildcard, even with a range before
+ -[a-zA-Z0-9]|--[a-zA-Z0-9]*=*)
+ printf 'Unknown option: %s\n' "$i"
+ exit 2
+ ;;
+ *)
+ break
+ ;;
+ esac
+ done
+ name="$1"; shift
+ exp_out="$1"; shift
+
+ [ -z "${name}" ] && name="$*"
+
+ # Append a final slash so sh(1) doesn't trims final newlines
+ out="$("$@" 2>&1;r=$?;printf %s /;exit $r)"
+ ret="$?"
+ out="${out%/}"
+
+ count=$((count+1))
+
+ if [ "$ret" != "$exp_ret" ]; then
+ printf 'not ok %d - %s\n' "$count" "$name"
+ printf '# Expected exit code %d, got %d\n' "$exp_ret" "$ret"
+ printf '# %s\n' "$out" | sed -e 's;^[^#];# ;'
+ err=1
+ elif [ "$out" != "$exp_out" ]; then
+ printf 'not ok %d - %s\n' "$count" "$name"
+ printf '# == Expected ==\n'
+ printf '# %s\n' "$exp_out" | sed -e 's;^[^#];# ;'
+ printf '# == Got ==\n'
+ printf '# %s\n' "$out" | sed -e 's;^[^#];# ;'
+ err=1
+ else
+ printf 'ok %d - %s\n' "$count" "$name"
+ fi
+}
+
+t_end()
+{
+ if [ $count -ne $plans ]
+ then
+ printf 'error: Ran %d instead of the planned %d tests\n' "$count" "$plans" >&2
+ err=1
+ fi
+
+ exit $err
+}
+
+# $1 -> name
+# $2 -> reason for skipping
+skip()
+{
+ count=$((count+1))
+ name="$1"
+ shift
+ printf 'ok %s # skip %s\n' "$count $name" "$*"
+}
+
+if ! test -f "${target?}"; then
+ printf '1..0 # SKIP: missing executable: %s\n' "${target?}"
+ exit 0
+fi
+
+printf '1..%d\n' "$plans"
+
+trap t_end EXIT
diff --git a/test.sh b/test.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+# Copyright © 2025 Haelwenn (lanodan) Monnier <contact+cmd-cidr@hacktivis.me>
+# SPDX-License-Identifier: MPL-2.0
+
+plans=8
+WD=$(dirname "$0")
+target="${WD}/cidr2list"
+. ./tap.sh
+set -e
+
+lines() {
+ echo "$@" | "$target" | wc -l | tr -d '\n'
+}
+
+t_cmd lines:/32 1 lines 192.168.0.42/32
+t_cmd lines:/31 2 lines 192.168.0.42/31
+t_cmd lines:/30 4 lines 192.168.0.42/30
+t_cmd lines:/24 256 lines 192.168.0.42/24
+t_cmd lines:/22 1024 lines 192.168.0.42/22
+t_cmd lines:/16 65536 lines 192.168.0.42/16
+
+t --input='192.168.0.42/31' 192.168.0.42/31 '192.168.0.42
+192.168.0.43
+'
+t --input='192.168.0.43/31' 192.168.0.43/31 '192.168.0.42
+192.168.0.43
+'
