git mv src/content/* src/content/en/

4 files changed, 0 insertions, 645 deletions

diff --git a/src/content/blog/2021/01/26/remembering-ann.adoc b/src/content/blog/2021/01/26/remembering-ann.adoc
deleted file mode 100644
index 6786b3c..0000000
--- a/src/content/blog/2021/01/26/remembering-ann.adoc
+++ /dev/null
@@ -1,216 +0,0 @@
-= ANN: remembering - Add memory to dmenu, fzf and similar tools
-:categories: ann
-
-:remembering: https://euandreh.xyz/remembering/
-:dmenu: https://tools.suckless.org/dmenu/
-:fzf: https://github.com/junegunn/fzf
-
-Today I pushed v0.1.0 of {remembering}[remembering], a tool to enhance the
-interactive usability of menu-like tools, such as {dmenu}[dmenu] and {fzf}[fzf].
-
-== Previous solution
-
-:yeganesh: https://dmwit.com/yeganesh/
-
-I previously used {yeganesh}[yeganesh] to fill this gap, but as I started to
-rely less on Emacs, I added fzf as my go-to tool for doing fuzzy searching on
-the terminal.  But I didn't like that fzf always showed the same order of
-things, when I would only need 3 or 4 commonly used files.
-
-For those who don't know: yeganesh is a wrapper around dmenu that will remember
-your most used programs and put them on the beginning of the list of
-executables.  This is very convenient for interactive prolonged use, as with
-time the things you usually want are right at the very beginning.
-
-But now I had this thing, yeganesh, that solved this problem for dmenu, but
-didn't for fzf.
-
-I initially considered patching yeganesh to support it, but I found it more
-coupled to dmenu than I would desire.  I'd rather have something that knows
-nothing about dmenu, fzf or anything, but enhances tools like those in a useful
-way.
-
-== Implementation
-
-:v-010: https://euandre.org/git/remembering/tree/remembering?id=v0.1.0
-:getopts: https://www.opengroup.org/onlinepubs/9699919799/utilities/getopts.html
-:sort: https://www.opengroup.org/onlinepubs/9699919799/utilities/sort.html
-:awk: https://www.opengroup.org/onlinepubs/9699919799/utilities/awk.html
-:spencer-quote: https://en.wikipedia.org/wiki/Henry_Spencer#cite_note-3
-
-Other than being decoupled from dmenu, another improvement I though that could
-be made on top of yeganesh is the programming language choice.  Instead of
-Haskell, I went with POSIX sh.  Sticking to POSIX sh makes it require less
-build-time dependencies.  There aren't any, actually.  Packaging is made much
-easier due to that.
-
-The good thing is that the program itself is small enough ({v-010}[119 lines] on
-v0.1.0) that POSIX sh does the job just fine, combined with other POSIX
-utilities such as {getopts}[getopts], {sort}[sort] and {awk}[awk].
-
-The behaviour is: given a program that will read from STDIN and write a single
-entry to STDOUT, `remembering` wraps that program, and rearranges STDIN so that
-previous choices appear at the beginning.
-
-Where you would do:
-
-[source,sh]
-----
-$ seq 5 | fzf
-
-  5
-  4
-  3
-  2
-> 1
-  5/5
->
-----
-
-And every time get the same order of numbers, now you can write:
-
-[source,sh]
-----
-$ seq 5 | remembering -p seq-fzf -c fzf
-
-  5
-  4
-  3
-  2
-> 1
-  5/5
->
-----
-
-On the first run, everything is the same.  If you picked 4 on the previous
-example, the following run would be different:
-
-[source,sh]
-----
-$ seq 5 | remembering -p seq-fzf -c fzf
-
-  5
-  3
-  2
-  1
-> 4
-  5/5
->
-----
-
-As time passes, the list would adjust based on the frequency of your choices.
-
-I aimed for reusability, so that I could wrap diverse commands with
-`remembering` and it would be able to work.  To accomplish that, a "profile"
-(the `-p something` part) stores data about different runs separately.
-
-I took the idea of building something small with few dependencies to other
-places too: - the manpages are written in troff directly; - the tests are just
-more POSIX sh files; - and a POSIX Makefile to `check` and `install`.
-
-I was aware of the value of sticking to coding to standards, but I had past
-experience mostly with programming language standards, such as ECMAScript,
-Common Lisp, Scheme, or with IndexedDB or DOM APIs.  It felt good to rediscover
-these nice POSIX tools, which makes me remember of a quote by
-{spencer-quote}[Henry Spencer]:
-
-____
-Those who do not understand Unix are condemned to reinvent it, poorly.
-____
-
-== Usage examples
-
-Here are some functions I wrote myself that you may find useful:
-
-=== Run a command with fzf on `$PWD`
-
-[source,sh]
-----
-f() {
-  profile="$f-shell-function(pwd | sed -e 's_/_-_g')"
-  file="$(git ls-files | \
-            remembering -p "$profile" \
-                        -c "fzf --select-1 --exit -0 --query \"$2\" --preview 'cat {}'")"
-  if [ -n "$file" ]; then
-    # shellcheck disable=2068
-    history -s f $@
-    history -s "$1" "$file"
-  "$1" "$file"
-fi
-}
-----
-
-This way I can run `f vi` or `f vi config` at the root of a repository, and the
-list of files will always appear on the most used order.  Adding `pwd` to the
-profile allows it to not mix data for different repositories.
-
-=== Copy password to clipboard
-
-:pass: https://www.passwordstore.org/
-
-[source,sh]
-----
-choice="$(find "$HOME/.password-store" -type f                  | \
-            grep -Ev '(.git|.gpg-id)'                           | \
-            sed -e "s|$HOME/.password-store/||" -e 's/\.gpg$//' | \
-            remembering -p password-store \
-                        -c 'dmenu -l 20 -i')"
-
-
-if [ -n "$choice" ]; then
-  pass show "$choice" -c
-fi
-----
-
-Adding the above to a file and binding it to a keyboard shortcut, I can access
-the contents of my {pass}[password store], with the entries ordered by usage.
-
-=== Replacing yeganesh
-
-Where I previously had:
-
-[source,sh]
-----
-exe=$(yeganesh -x) && exec $exe
-----
-
-Now I have:
-
-[source,sh]
-----
-exe=$(dmenu_path | remembering -p dmenu-exec -c dmenu) && exec $exe
-----
-
-This way, the executables appear on order of usage.
-
-If you don't have `dmenu_path`, you can get just the underlying `stest` tool
-that looks at the executables available in your `$PATH`.  Here's a juicy
-one-liner to do it:
-
-[source,sh]
-----
-$ wget -O- https://dl.suckless.org/tools/dmenu-5.0.tar.gz | \
-    tar Ozxf - dmenu-5.0/arg.h dmenu-5.0/stest.c          | \
-    sed 's|^#include "arg.h"$|// #include "arg.h"|'       | \
-    cc -xc - -o stest
-----
-
-With the `stest` utility you'll be able to list executables in your `$PATH` and
-pipe them to dmenu or something else yourself:
-
-[source,sh]
-----
-$ (IFS=:; ./stest -flx $PATH;) | sort -u | remembering -p another-dmenu-exec -c dmenu | sh
-----
-
-In fact, the code for `dmenu_path` is almost just like that.
-
-== Conclusion
-
-:packaged: https://euandre.org/git/package-repository/
-
-For my personal use, I've {packaged}[packaged] `remembering` for GNU Guix and
-Nix.  Packaging it to any other distribution should be trivial, or just
-downloading the tarball and running `[sudo] make install`.
-
-Patches welcome!
diff --git a/src/content/blog/2021/02/17/fallible.adoc b/src/content/blog/2021/02/17/fallible.adoc
deleted file mode 100644
index 1f2f641..0000000
--- a/src/content/blog/2021/02/17/fallible.adoc
+++ /dev/null
@@ -1,285 +0,0 @@
-= ANN: fallible - Fault injection library for stress-testing failure scenarios
-:updatedat: 2022-03-06
-
-:fallible: https://euandreh.xyz/fallible/
-
-Yesterday I pushed v0.1.0 of {fallible}[fallible], a miniscule library for
-fault-injection and stress-testing C programs.
-
-== _EDIT_
-
-:changelog: https://euandreh.xyz/fallible/CHANGELOG.html
-:tarball: https://euandre.org/static/attachments/fallible.tar.gz
-
-2021-06-12: As of {changelog}[0.3.0] (and beyond), the macro interface improved
-and is a bit different from what is presented in this article.  If you're
-interested, I encourage you to take a look at it.
-
-2022-03-06: I've {tarball}[archived] the project for now.  It still needs some
-maturing before being usable.
-
-== Existing solutions
-
-:gnu-std: https://www.gnu.org/prep/standards/standards.html#Semantics
-:valgrind: https://www.valgrind.org/
-:so-alloc: https://stackoverflow.com/questions/1711170/unit-testing-for-failed-malloc
-
-Writing robust code can be challenging, and tools like static analyzers, fuzzers
-and friends can help you get there with more certainty.  As I would try to
-improve some of my C code and make it more robust, in order to handle system
-crashes, filled disks, out-of-memory and similar scenarios, I didn't find
-existing tooling to help me get there as I expected to find.  I couldn't find
-existing tools to help me explicitly stress-test those failure scenarios.
-
-Take the "{gnu-std}[Writing Robust Programs]" section of the GNU Coding
-Standards:
-
-____
-Check every system call for an error return, unless you know you wish to ignore
-errors.  (...) Check every call to malloc or realloc to see if it returned NULL.
-____
-
-From a robustness standpoint, this is a reasonable stance: if you want to have a
-robust program that knows how to fail when you're out of memory and `malloc`
-returns `NULL`, than you ought to check every call to `malloc`.
-
-Take a sample code snippet for clarity:
-
-[source,c]
-----
-void a_function() {
-  char *s1 = malloc(A_NUMBER);
-  strcpy(s1, "some string");
-
-  char *s2 = malloc(A_NUMBER);
-  strcpy(s2, "another string");
-}
-----
-
-At a first glance, this code is unsafe: if any of the calls to `malloc` returns
-`NULL`, `strcpy` will be given a `NULL` pointer.
-
-My first instinct was to change this code to something like this:
-
-[source,diff]
-----
-@@ -1,7 +1,15 @@
- void a_function() {
-   char *s1 = malloc(A_NUMBER);
-+  if (!s1) {
-+    fprintf(stderr, "out of memory, exitting\n");
-+    exit(1);
-+  }
-   strcpy(s1, "some string");
-
-   char *s2 = malloc(A_NUMBER);
-+  if (!s2) {
-+    fprintf(stderr, "out of memory, exitting\n");
-+    exit(1);
-+  }
-   strcpy(s2, "another string");
- }
-----
-
-As I later found out, there are at least 2 problems with this approach:
-
-. *it doesn't compose*: this could arguably work if `a_function` was `main`.
-  But if `a_function` lives inside a library, an `exit(1);` is an inelegant way
-  of handling failures, and will catch the top-level `main` consuming the
-  library by surprise;
-. *it gives up instead of handling failures*: the actual handling goes a bit
-  beyond stopping.  What about open file handles, in-memory caches, unflushed
-  bytes, etc.?
-
-If you could force only the second call to `malloc` to fail,
-{valgrind}[Valgrind] would correctly complain that the program exitted with
-unfreed memory.
-
-So the last change to make the best version of the above code is:
-
-[source,diff]
-----
-@@ -1,15 +1,14 @@
--void a_function() {
-+bool a_function() {
-   char *s1 = malloc(A_NUMBER);
-   if (!s1) {
--    fprintf(stderr, "out of memory, exitting\n");
--    exit(1);
-+    return false;
-   }
-   strcpy(s1, "some string");
-
-   char *s2 = malloc(A_NUMBER);
-   if (!s2) {
--    fprintf(stderr, "out of memory, exitting\n");
--    exit(1);
-+    free(s1);
-+    return false;
-   }
-   strcpy(s2, "another string");
- }
-----
-
-Instead of returning `void`, `a_function` now returns `bool` to indicate whether
-an error ocurred during its execution.  If `a_function` returned a pointer to
-something, the return value could be `NULL`, or an `int` that represents an
-error code.
-
-The code is now a) safe and b) failing gracefully, returning the control to the
-caller to properly handle the error case.
-
-After seeing similar patterns on well designed APIs, I adopted this practice for
-my own code, but was still left with manually verifying the correctness and
-robustness of it.
-
-How could I add assertions around my code that would help me make sure the
-`free(s1);` exists, before getting an error report?  How do other people and
-projects solve this?
-
-From what I could see, either people a) hope for the best, b) write safe code
-but don't strees-test it or c) write ad-hoc code to stress it.
-
-The most proeminent case of c) is SQLite: it has a few wrappers around the
-familiar `malloc` to do fault injection, check for memory limits, add warnings,
-create shim layers for other environments, etc.  All of that, however, is
-tightly couple with SQLite itself, and couldn't be easily pulled off for using
-somewhere else.
-
-When searching for it online, an {so-alloc}[interesting thread] caught my
-atention: fail the call to `malloc` for each time it is called, and when the
-same stacktrace appears again, allow it to proceed.
-
-== Implementation
-
-:mallocfail: https://github.com/ralight/mallocfail
-:should-fail-fn: https://euandre.org/git/fallible/tree/src/fallible.c?id=v0.1.0#n16
-
-A working implementation of that already exists: {mallocfail}[mallocfail].  It
-uses `LD_PRELOAD` to replace `malloc` at run-time, computes the SHA of the
-stacktrace and fails once for each SHA.
-
-I initially envisioned and started implementing something very similar to
-mallocfail.  However I wanted it to go beyond out-of-memory scenarios, and using
-`LD_PRELOAD` for every possible corner that could fail wasn't a good idea on the
-long run.
-
-Also, mallocfail won't work together with tools such as Valgrind, who want to do
-their own override of `malloc` with `LD_PRELOAD`.
-
-I instead went with less automatic things: starting with a
-`fallible_should_fail(char *filename, int lineno)` function that fails once for
-each `filename`+`lineno` combination, I created macro wrappers around common
-functions such as `malloc`:
-
-[source,c]
-----
-void *fallible_malloc(size_t size, const char *const filename, int lineno) {
-#ifdef FALLIBLE
-  if (fallible_should_fail(filename, lineno)) {
-    return NULL;
-  }
-#else
-  (void)filename;
-  (void)lineno;
-#endif
-  return malloc(size);
-}
-
-#define MALLOC(size) fallible_malloc(size, __FILE__, __LINE__)
-----
-
-With this definition, I could replace the calls to `malloc` with `MALLOC` (or
-any other name that you want to `#define`):
-
-[source,diff]
-----
---- 3.c 2021-02-17 00:15:38.019706074 -0300
-+++ 4.c 2021-02-17 00:44:32.306885590 -0300
-@@ -1,11 +1,11 @@
- bool a_function() {
--  char *s1 = malloc(A_NUMBER);
-+  char *s1 = MALLOC(A_NUMBER);
-   if (!s1) {
-     return false;
-   }
-   strcpy(s1, "some string");
-
--  char *s2 = malloc(A_NUMBER);
-+  char *s2 = MALLOC(A_NUMBER);
-   if (!s2) {
-     free(s1);
-     return false;
-----
-
-With this change, if the program gets compiled with the `-DFALLIBLE` flag the
-fault-injection mechanism will run, and `MALLOC` will fail once for each
-`filename`+`lineno` combination.  When the flag is missing, `MALLOC` is a very
-thin wrapper around `malloc`, which compilers could remove entirely, and the
-`-lfallible` flags can be omitted.
-
-This applies not only to `malloc` or other `stdlib.h` functions.  If
-`a_function` is important or relevant, I could add a wrapper around it too, that
-checks if `fallible_should_fail` to exercise if its callers are also doing the
-proper clean-up.
-
-The actual code is just this single function,
-{should-fail-fn}[`fallible_should_fail`], which ended-up taking only ~40 lines.
-In fact, there are more lines of either Makefile (111), README.md (82) or troff
-(306) on this first version.
-
-The price for such fine-grained control is that this approach requires more
-manual work.
-
-== Usage examples
-
-=== `MALLOC` from the `README.md`
-
-:fallible-check: https://euandreh.xyz/fallible/fallible-check.1.html
-
-[source,c]
-----
-// leaky.c
-#include <string.h>
-#include <fallible_alloc.h>
-
-int main() {
-  char *aaa = MALLOC(100);
-  if (!aaa) {
-    return 1;
-  }
-  strcpy(aaa, "a safe use of strcpy");
-
-  char *bbb = MALLOC(100);
-  if (!bbb) {
-    // free(aaa);
-    return 1;
-  }
-  strcpy(bbb, "not unsafe, but aaa is leaking");
-
-  free(bbb);
-  free(aaa);
-  return 0;
-}
-----
-
-Compile with `-DFALLIBLE` and run {fallible-check}[`fallible-check.1`]:
-
-[source,sh]
-----
-$ c99 -DFALLIBLE -o leaky leaky.c -lfallible
-$ fallible-check ./leaky
-Valgrind failed when we did not expect it to:
-(...suppressed output...)
-# exit status is 1
-----
-
-== Conclusion
-
-:package: https://euandre.org/git/package-repository/
-
-For my personal use, I'll {package}[package] them for GNU Guix and Nix.
-Packaging it to any other distribution should be trivial, or just downloading
-the tarball and running `[sudo] make install`.
-
-Patches welcome!
diff --git a/src/content/blog/2021/02/17/fallible.tar.gz b/src/content/blog/2021/02/17/fallible.tar.gz
deleted file mode 100644
index 211cadd..0000000
--- a/src/content/blog/2021/02/17/fallible.tar.gz
+++ /dev/null
diff --git a/src/content/blog/2021/04/29/relational-review.adoc b/src/content/blog/2021/04/29/relational-review.adoc
deleted file mode 100644
index 4b53737..0000000
--- a/src/content/blog/2021/04/29/relational-review.adoc
+++ /dev/null
@@ -1,144 +0,0 @@
-= A Relational Model of Data for Large Shared Data Banks - article-review
-
-:empty:
-:reviewed-article: https://www.seas.upenn.edu/~zives/03f/cis550/codd.pdf
-
-This is a review of the article "{reviewed-article}[A Relational Model of Data
-for Large Shared Data Banks]", by E. F. Codd.
-
-== Data Independence
-
-Codd brings the idea of _data independence_ as a better approach to use on
-databases.  This is contrast with the existing approaches, namely hierarquical
-(tree-based) and network-based.
-
-His main argument is that queries in applications shouldn't depende and be
-coupled with how the data is represented internally by the database system.
-This key idea is very powerful, and something that we strive for in many other
-places: decoupling the interface from the implementation.
-
-If the database system has this separation, it can kep the querying interface
-stable, while having the freedom to change its internal representation at will,
-for better performance, less storage, etc.
-
-This is true for most modern database systems.  They can change from B-Trees
-with leafs containing pointers to data, to B-Trees with leafs containing the raw
-data , to hash tables.  All that without changing the query interface, only its
-performance.
-
-Codd mentions that, from an information representation standpoint, any index is
-a duplication, but useful for perfomance.
-
-This data independence also impacts ordering (a _relation_ doesn't rely on the
-insertion order).
-
-== Duplicates
-
-His definition of relational data is a bit differente from most modern database
-systems, namely *no duplicate rows*.
-
-I couldn't find a reason behind this restriction, though.  For practical
-purposes, I find it useful to have it.
-
-== Relational Data
-
-:edn: https://github.com/edn-format/edn
-
-In the article, Codd doesn't try to define a language, and today's most popular
-one is SQL.
-
-However, there is no restriction that says that "SQL database" and "relational
-database" are synonyms.  One could have a relational database without using SQL
-at all, and it would still be a relational one.
-
-The main one that I have in mind, and the reason that led me to reading this
-paper in the first place, is Datomic.
-
-Is uses an {edn}[edn]-based representation for datalog
-queries{empty}footnote:edn-queries[
-  You can think of it as JSON, but with a Clojure taste.
-], and a particular schema used to represent data.
-
-Even though it looks very weird when coming from SQL, I'd argue that it ticks
-all the boxes (except for "no duplicates") that defines a relational database,
-since building relations and applying operations on them is possible.
-
-Compare and contrast a contrived example of possible representations of SQL and
-datalog of the same data:
-
-[source,sql]
-----
--- create schema
-CREATE TABLE people (
-  id UUID PRIMARY KEY,
-  name TEXT NOT NULL,
-  manager_id UUID,
-  FOREIGN KEY (manager_id) REFERENCES people (id)
-);
-
--- insert data
-INSERT INTO people (id, name, manager_id) VALUES
-  ("d3f29960-ccf0-44e4-be66-1a1544677441", "Foo", "076356f4-1a0e-451c-b9c6-a6f56feec941"),
-  ("076356f4-1a0e-451c-b9c6-a6f56feec941", "Bar");
-
--- query data, make a relation
-
-SELECT employees.name AS 'employee-name',
-       managers.name AS 'manager-name'
-FROM people employees
-INNER JOIN people managers ON employees.manager_id = managers.id;
-----
-
-[source,clojure]
-----
-;; create schema
-#{{:db/ident       :person/id
-   :db/valueType   :db.type/uuid
-   :db/cardinality :db.cardinality/one
-   :db/unique      :db.unique/value}
-  {:db/ident       :person/name
-   :db/valueType   :db.type/string
-   :db/cardinality :db.cardinality/one}
-  {:db/ident       :person/manager
-   :db/valueType   :db.type/ref
-   :db/cardinality :db.cardinality/one}}
-
-;; insert data
-#{{:person/id      #uuid "d3f29960-ccf0-44e4-be66-1a1544677441"
-   :person/name    "Foo"
-   :person/manager [:person/id #uuid "076356f4-1a0e-451c-b9c6-a6f56feec941"]}
-  {:person/id      #uuid "076356f4-1a0e-451c-b9c6-a6f56feec941"
-   :person/name    "Bar"}}
-
-;; query data, make a relation
-{:find [?employee-name ?manager-name]
- :where [[?person  :person/name    ?employee-name]
-         [?person  :person/manager ?manager]
-         [?manager :person/name    ?manager-name]]}
-----
-
-(forgive any errors on the above SQL and datalog code, I didn't run them to
-check.  Patches welcome!)
-
-This employee example comes from the paper, and both SQL and datalog
-representations match the paper definition of "relational".
-
-Both "Foo" and "Bar" are employees, and the data is normalized.  SQL represents
-data as tables, and Datomic as datoms, but relations could be derived from both,
-which we could view as:
-
-[source,sql]
-----
-employee_name | manager_name
-----------------------------
-"Foo"         | "Bar"
-----
-
-== Conclusion
-
-The article also talks about operators, consistency and normalization, which are
-now so widespread and well-known that it feels a bit weird seeing someone
-advocating for it.
-
-I also stablish that `relational != SQL`, and other databases such as Datomic
-are also relational, following Codd's original definition.