5 files changed, 106 insertions, 11 deletions
diff --git a/.travis.yml b/.travis.yml
index 81eb2492..e62f843f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,10 +2,12 @@ language: c
 notifications:
     irc: "chat.freenode.net#krebs_incoming"
 
-script: "make -C util test | grep -q '^not ok' && exit 1"
+script: "! ( make -C util test | grep -q '^not ok' )"
 before_install:
   - sudo apt-get install bc -qq
   - sudo apt-get install python -qq
 branches:
     only:
         - master
+git:
+    submodules: false
diff --git a/cholerab/ledger-spec.markdown b/cholerab/ledger-spec.markdown
index 15a290bf..812bce33 100644
--- a/cholerab/ledger-spec.markdown
+++ b/cholerab/ledger-spec.markdown
@@ -1,8 +1,16 @@
-# Format
+# Ledger Specification
+
+## Transaction Record
+
+### External Representation
 
     DATE DESTINATION-ACCOUNT SOURCE-ACCOUNT AMOUNT UNIT [COMMENT...]
 
-# Example
+  where
+  - `DATE` has the form `YYYY-MM-DD`
+  - `AMOUNT` is a non-negative, decimal number
+
+### Example
 
     2013-01-01 krebs-ml amazon 30 EUR C0DE-AAAA-BBBB-CCCC
     2013-02-02 momo krebs-ml 50 EUR C0DE-AAAA-BBBB-CCCC
diff --git a/ledger/lib/balance b/ledger/lib/balance
new file mode 100755
index 00000000..77cb7f6d
--- /dev/null
+++ b/ledger/lib/balance
@@ -0,0 +1,85 @@
+#! /bin/awk -f
+#
+# ledger balance calculator
+#
+# usage:
+#   [colorize=false] [scale=N] //ledger/lib/balance LEDGER_FILE...
+#   [colorize=false] [scale=N] //ledger/lib/balance < LEDGER_FILE
+#
+# description:
+#   The ledger balance calculator computes the balance of each account it
+#   encounters in the provided ledger files.
+#
+# example:
+#   //ledger/lib/balance < //cholerab/ledger-spec.markdown
+#
+# see also:
+#   //cholerab/ledger-spec.markdown (ledger file format)
+#
+
+BEGIN {
+  colorize = ENVIRON["colorize"] == "" || ENVIRON["colorize"] == "true"
+  # TODO use bc for arbitrary precision arithmetic
+  scale = ENVIRON["scale"]
+}
+
+/^[[:space:]]*[0-9]+-[0-9][0-9]-[0-9][0-9]/{
+  tx($2, $3, $4, $5)
+}
+
+END {
+  display_accounts()
+}
+
+function tx (dst, src, amt, u) {
+  withdraw(src, amt, u)
+  deposit(dst, amt, u)
+}
+
+function deposit (name, amt, u) {
+  accounts[name][u] += amt
+}
+
+function withdraw (name, amt, u) {
+  accounts[name][u] -= amt
+}
+
+function display_accounts() {
+  max_name_len = 0
+  for (name in accounts) {
+    if (length(name) > max_name_len) {
+      max_name_len = length(name)
+    }
+  }
+
+  max_balance_len = 0
+  for (name in accounts) {
+    for (u in accounts[name]) {
+      n = length(int(accounts[name][u]))
+      if (n > max_balance_len) {
+        max_balance_len = n
+      }
+    }
+  }
+  if (scale > 0) {
+    max_balance_len += length(".") + scale
+  }
+
+  for (name in accounts) {
+    for (u in accounts[name]) {
+
+      fmt = "NAME BALANCE UNIT\n"
+      balance = accounts[name][u]
+
+      if (colorize) {
+        sub("BALANCE", "[" (balance < 0 ? 31 : 32) "m&[m", fmt)
+      }
+
+      sub("NAME", "%-" max_name_len "s", fmt)
+      sub("BALANCE", "%" max_balance_len "." scale "f", fmt)
+      sub("UNIT", "%s", fmt)
+
+      printf fmt, name, balance, u
+    }
+  }
+}
diff --git a/util/t/uriparse/parse-retard-uri b/util/t/uriparse/parse-retard-uri
index 0c149148..76feac41 100755
--- a/util/t/uriparse/parse-retard-uri
+++ b/util/t/uriparse/parse-retard-uri
@@ -5,9 +5,9 @@ trap "/bin/rm -f $tempfile" EXIT INT
 
 uriparse "http://'lolwut:\"khan@domain.tld/'''" > $tempfile
 . $tempfile
-[ "$HOSTN" == "domain.tld" ] && \
-    [ "$USERNAME" == "'lolwut" ] && \
-    [ "$PASSWORD" == '"khan' ] && \
-    [ "$URIPATH" == "/'''" ] 
+[ "$HOSTN" = "domain.tld" ] && \
+    [ "$USERNAME" = "'lolwut" ] && \
+    [ "$PASSWORD" = '"khan' ] && \
+    [ "$URIPATH" = "/'''" ] 
 
 
diff --git a/util/t/uriparse/parse-url b/util/t/uriparse/parse-url
index cf6f53fd..2ccf39c9 100755
--- a/util/t/uriparse/parse-url
+++ b/util/t/uriparse/parse-url
@@ -5,9 +5,9 @@ trap "/bin/rm -f $tempfile" EXIT INT
 
 uriparse "http://user:pass@domain.tld/path" > $tempfile
 . $tempfile
-[ "$HOSTN" == "domain.tld" ] && \
-    [ $USERNAME == "user" ] && \
-    [ $PASSWORD == "pass" ] && \
-    [ $URIPATH == "/path" ] 
+[ "$HOSTN" = "domain.tld" ] && \
+    [ $USERNAME = "user" ] && \
+    [ $PASSWORD = "pass" ] && \
+    [ $URIPATH  = "/path" ]