1 files changed, 61 insertions, 0 deletions
diff --git a/lib/pure/parseutils.nim b/lib/pure/parseutils.nim
index 698bde42a..fb7d72182 100644
--- a/lib/pure/parseutils.nim
+++ b/lib/pure/parseutils.nim
@@ -173,6 +173,22 @@ proc parseUntil*(s: string, token: var string, until: char,
   result = i-start
   token = substr(s, start, i-1)
 
+proc parseUntil*(s: string, token: var string, until: string,
+                 start = 0): int {.inline.} =
+  ## parses a token and stores it in ``token``. Returns
+  ## the number of the parsed characters or 0 in case of an error. A token
+  ## consists of any character that comes before the `until`  token.
+  var i = start
+  while i < s.len:
+    if s[i] == until[0]:
+      var u = 1
+      while i+u < s.len and u < until.len and s[i+u] == until[u]:
+        inc u
+      if u >= until.len: break
+    inc(i)
+  result = i-start
+  token = substr(s, start, i-1)
+
 proc parseWhile*(s: string, token: var string, validChars: set[char],
                  start = 0): int {.inline.} =
   ## parses a token and stores it in ``token``. Returns
@@ -234,6 +250,51 @@ proc parseInt*(s: string, number: var int, start = 0): int {.
   elif result != 0:
     number = int(res)
 
+# overflowChecks doesn't work with uint64
+proc rawParseUInt(s: string, b: var uint64, start = 0): int =
+  var
+    res = 0'u64
+    prev = 0'u64
+    i = start
+  if s[i] == '+': inc(i) # Allow
+  if s[i] in {'0'..'9'}:
+    b = 0
+    while s[i] in {'0'..'9'}:
+      prev = res
+      res = res * 10 + (ord(s[i]) - ord('0')).uint64
+      if prev > res:
+        return 0 # overflowChecks emulation
+      inc(i)
+      while s[i] == '_': inc(i) # underscores are allowed and ignored
+    b = res
+    result = i - start
+
+proc parseBiggestUInt*(s: string, number: var uint64, start = 0): int {.
+  rtl, extern: "npuParseBiggestUInt", noSideEffect.} =
+  ## parses an unsigned integer starting at `start` and stores the value
+  ## into `number`.
+  ## Result is the number of processed chars or 0 if there is no integer
+  ## or overflow detected.
+  var res: uint64
+  # use 'res' for exception safety (don't write to 'number' in case of an
+  # overflow exception):
+  result = rawParseUInt(s, res, start)
+  number = res
+
+proc parseUInt*(s: string, number: var uint, start = 0): int {.
+  rtl, extern: "npuParseUInt", noSideEffect.} =
+  ## parses an unsigned integer starting at `start` and stores the value
+  ## into `number`.
+  ## Result is the number of processed chars or 0 if there is no integer or
+  ## overflow detected.
+  var res: uint64
+  result = parseBiggestUInt(s, res, start)
+  if (sizeof(uint) <= 4) and
+      (res > 0xFFFF_FFFF'u64):
+    raise newException(OverflowError, "overflow")
+  elif result != 0:
+    number = uint(res)
+
 proc parseBiggestFloat*(s: string, number: var BiggestFloat, start = 0): int {.
   magic: "ParseBiggestFloat", importc: "nimParseBiggestFloat", noSideEffect.}
   ## parses a float starting at `start` and stores the value into `number`.