extensive rewrite to use json for storage:

sqlite3 requires the directory where the database resides to be
writeable by the user. This presents a problem on multiuser UNIX systems
where they may want to limit areas where users have write access.

This rewrite totally scraps the sqlite3 database in favor of a pretty
simple json file consisting of an array of posts. flock(2) locking is
used to synchronize access to the file and make sure two clients aren't
trying to write to it at once. The locking is fairly granular right now,
but later I may change it to using a single lock for the duration of
execution since race conditions are *possible*, if unlikely for the
purposes of clinte's intended use.

1 files changed, 157 insertions, 62 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 9b8762d..9ccdc25 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,6 +1,14 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
 [[package]]
+name = "addr2line"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "gimli 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "ansi_term"
 version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -34,6 +42,18 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "backtrace"
+version = "0.3.48"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "addr2line 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "object 0.19.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "base64"
 version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -87,9 +107,11 @@ version = "1.0.0"
 dependencies = [
  "chrono 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fd-lock 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "rusqlite 0.20.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.53 (registry+https://github.com/rust-lang/crates.io-index)",
  "simplelog 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "users 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -129,14 +151,34 @@ dependencies = [
 ]
 
 [[package]]
-name = "fallible-iterator"
-version = "0.2.0"
+name = "failure"
+version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "backtrace 0.3.48 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure_derive 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
-name = "fallible-streaming-iterator"
-version = "0.1.9"
+name = "failure_derive"
+version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "synstructure 0.12.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "fd-lock"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "failure 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.66 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "getrandom"
@@ -149,6 +191,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "gimli"
+version = "0.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "hermit-abi"
 version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -157,6 +204,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "itoa"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "lazy_static"
 version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -167,20 +219,6 @@ version = "0.2.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "libsqlite3-sys"
-version = "0.16.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "pkg-config 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)",
- "vcpkg 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "linked-hash-map"
-version = "0.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "log"
 version = "0.4.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -189,19 +227,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "lru-cache"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "linked-hash-map 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "memchr"
-version = "2.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "num-integer"
 version = "0.1.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -219,9 +244,25 @@ dependencies = [
 ]
 
 [[package]]
-name = "pkg-config"
-version = "0.3.17"
+name = "object"
+version = "0.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "redox_syscall"
@@ -239,20 +280,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "rusqlite"
-version = "0.20.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "fallible-iterator 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "fallible-streaming-iterator 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "libsqlite3-sys 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "lru-cache 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "rust-argon2"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -264,6 +291,44 @@ dependencies = [
 ]
 
 [[package]]
+name = "rustc-demangle"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "ryu"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "serde"
+version = "1.0.110"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde_derive 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.110"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "serde_json"
+version = "1.0.53"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "itoa 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ryu 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "simplelog"
 version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -279,6 +344,27 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "syn"
+version = "1.0.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "synstructure"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "term"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -311,6 +397,11 @@ version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "unicode-xid"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "users"
 version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -319,11 +410,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "vcpkg"
-version = "0.2.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -348,11 +434,13 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
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+"checksum addr2line 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a49806b9dadc843c61e7c97e72490ad7f7220ae249012fbda9ad0609457c0543"
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 "checksum autocfg 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
+"checksum backtrace 0.3.48 (registry+https://github.com/rust-lang/crates.io-index)" = "0df2f85c8a2abbe3b7d7e748052fdd9b76a0458fdeb16ad4223f5eca78c7c130"
 "checksum base64 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b41b7ea54a0c9d92199de89e20e58d49f02f8e699814ef3fdf266f6f748d15c7"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
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