Conversion functions

include/malunal/strview.h

@@ -4,7 +4,7 @@
  * @author John Christman (sorakatadzuma@gmail.com)
  * @copyright Malunal Studios, LLC.
  */
-#include "malunal/type.h"
+#include "malunal/types/error.h"
 
 #ifndef MALUNAL_STRVIEW_HEADER
 #define MALUNAL_STRVIEW_HEADER
@@ -18,6 +18,14 @@
  */
 #define STRVIEW_NPOS ((malunal_size_t)-1)
 
+/**
+ * @brief   Imports the @c strview_t error domain for error checking.
+ * @details The @c strview_t error domain is specific for string views to
+ *          indicate an issue with functions relating to string views.
+ */
+extern
+const error_domain_t
+ERROR_DOMAIN_STRVIEW_T;
 
 /**
  * @struct  strview
@@ -43,6 +51,20 @@ define_struct(strview) {
   malunal_cstr_t end;
 };
 
+
+/**
+ * @brief   Defines the set of errors that may be triggered by a string view.
+ * @details This are used in conjunction with a domain to indicate an error
+ *          that comes specifically from a string view or its functions and
+ *          what that error means.
+ */
+typedef enum {
+  STRVIEW_ERROR_NULL_INPUT,
+  STRVIEW_ERROR_OUT_OF_RANGE,
+  STRVIEW_ERROR_UNCONSUMED,
+} strview_error_t;
+
+
 /**
  * @brief   Creates a string view from the provided @c data and @c length.
  * @param   data   A pointer to the data of the string view.
@@ -185,4 +207,28 @@ strview_contains(
   strview_iptr_t other
 );
 
+/**
+ * @brief   Converts the string view to an @c long @c long, ala @c strtoll.
+ * @param   self The string view to convert.
+ * @param   out  If not null, populated with the converted value.
+ * @returns An error if the conversion could not be performed.
+ */
+error_t
+strview_to_int64(
+  strview_iptr_t   self,
+  malunal_int64_t* out
+);
+
+/**
+ * @brief   Converts the string view to a @c float, ala @c strtod.
+ * @param   self The string view to convert.
+ * @param   out  If not null, populated with the converted value.
+ * @returns An error if the conversion could not be performed.
+ */
+error_t
+strview_to_double(
+  strview_iptr_t    self,
+  malunal_double_t* out
+);
+
 #endif /* MALUNAL_STRVIEW_HEADER */

sources/strview.c

@@ -1,6 +1,47 @@
+#include <errno.h>
+#include <stdlib.h>
 #include <string.h>
 #include "malunal/strview.h"
 
+#define STRVIEW_NUMBUF_SIZE 64
+
+static
+malunal_cstr_t
+describe(malunal_int32_t code) {
+  switch (code) {
+  case STRVIEW_ERROR_NULL_INPUT:
+    return "String view input was null.";
+  case STRVIEW_ERROR_OUT_OF_RANGE:
+    return "Conversion of string view to value was out of range.";
+  case STRVIEW_ERROR_UNCONSUMED:
+    return "String view was not consumed fully during conversion.";
+  }
+
+  return "Unknown strview error";
+}
+
+const error_domain_t ERROR_DOMAIN_STRVIEW_T = {
+  .describe = &describe,
+  .name     = "malunal.strview.error"
+};
+
+static malunal_size_t
+strview__copy_to_buffer(
+  strview_iptr_t self,
+  malunal_char_t buffer[STRVIEW_NUMBUF_SIZE]
+) {
+  malunal_size_t length = strview_length(self);
+  malunal_size_t copied =
+    length >= STRVIEW_NUMBUF_SIZE - 1
+      ? STRVIEW_NUMBUF_SIZE - 1
+      : length;
+
+  if (copied > 0)
+    memcpy(buffer, self->beg, copied);
+  buffer[copied] = '\0';
+  return copied;
+}
+
 
 strview_t
 strview(
@@ -178,3 +219,97 @@ strview_contains(
 
   return false;
 }
+
+error_t
+strview_to_int64(
+  strview_iptr_t   self,
+  malunal_int64_t* out
+) {
+  if (self == null) {
+    if (out != null)
+      *out = 0;
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_NULL_INPUT
+    };
+  }
+
+  malunal_char_t buffer[STRVIEW_NUMBUF_SIZE];
+  malunal_size_t copied = strview__copy_to_buffer(self, buffer);
+  if (copied == 0) {
+    if (out != null)
+      *out = 0;
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_UNCONSUMED
+    };
+  }
+
+  malunal_str_t   endptr;
+  malunal_int64_t value;
+
+  errno = 0;
+  value = strtoll(buffer, &endptr, 10);
+  if (out != null)
+    *out = value;
+
+  if (errno == ERANGE)
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_OUT_OF_RANGE
+    };
+
+  return endptr != buffer + copied
+    ? (error_t) {
+        .domain = &ERROR_DOMAIN_STRVIEW_T,
+        .code   = STRVIEW_ERROR_UNCONSUMED
+      }
+    : NO_ERROR;
+}
+
+error_t
+strview_to_double(
+  strview_iptr_t    self,
+  malunal_double_t* out
+) {
+  if (self == null) {
+    if (out != null)
+      *out = 0.0;
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_NULL_INPUT
+    };
+  }
+
+  malunal_char_t buffer[STRVIEW_NUMBUF_SIZE];
+  malunal_size_t copied = strview__copy_to_buffer(self, buffer);
+  if (copied == 0) {
+    if (out != null)
+      *out = 0.0;
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_UNCONSUMED
+    };
+  }
+
+  malunal_str_t    endptr;
+  malunal_double_t value;
+
+  errno = 0;
+  value = strtod(buffer, &endptr);
+  if (out != null)
+    *out = value;
+
+  if (errno == ERANGE)
+    return (error_t) {
+      .domain = &ERROR_DOMAIN_STRVIEW_T,
+      .code   = STRVIEW_ERROR_OUT_OF_RANGE
+    };
+
+  return endptr != buffer + copied
+    ? (error_t) {
+        .domain = &ERROR_DOMAIN_STRVIEW_T,
+        .code   = STRVIEW_ERROR_UNCONSUMED
+      }
+    : NO_ERROR;
+}

tests/strview.c

@@ -366,6 +366,201 @@ MICROTEST(strview_contains, false_when_other_longer_than_self) {
   MICROTEST_EXPECT_FALSE(strview_contains(&self, &other));
 }
 
+/* -------------------------------------------------------------------------
+ * strview_to_int64()
+ * ---------------------------------------------------------------------- */
+
+MICROTEST(strview_to_int64, positive_integer_succeeds) {
+  strview_t       view = strview_from_cstr("12345");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(out, (malunal_int64_t)12345);
+}
+
+MICROTEST(strview_to_int64, negative_integer_succeeds) {
+  strview_t       view = strview_from_cstr("-42");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(out, (malunal_int64_t)-42);
+}
+
+MICROTEST(strview_to_int64, zero_succeeds) {
+  strview_t       view = strview_from_cstr("0");
+  malunal_int64_t out  = -1;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(out, (malunal_int64_t)0);
+}
+
+MICROTEST(strview_to_int64, succeeds_on_subview_not_ending_at_buffer_end) {
+  malunal_cstr_t  data = "12345 and then some trailing text";
+  strview_t       view = strview(data, 5);
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(out, (malunal_int64_t)12345);
+}
+
+MICROTEST(strview_to_int64, trailing_garbage_reports_unconsumed) {
+  strview_t       view = strview_from_cstr("123abc");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_int64, non_numeric_reports_unconsumed) {
+  strview_t       view = strview_from_cstr("abc");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_int64, empty_view_reports_unconsumed) {
+  strview_t       view = strview_from_cstr("");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_int64, null_self_reports_null_input) {
+  malunal_int64_t out = 99;
+  error_t         err = strview_to_int64(null, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_NULL_INPUT);
+  MICROTEST_EXPECT_EQ(out, (malunal_int64_t)0);
+}
+
+MICROTEST(strview_to_int64, overflow_reports_out_of_range) {
+  strview_t       view = strview_from_cstr("99999999999999999999999");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_OUT_OF_RANGE);
+}
+
+MICROTEST(strview_to_int64, underflow_reports_out_of_range) {
+  strview_t       view = strview_from_cstr("-99999999999999999999999");
+  malunal_int64_t out  = 0;
+  error_t         err  = strview_to_int64(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_OUT_OF_RANGE);
+}
+
+MICROTEST(strview_to_int64, null_out_pointer_does_not_crash) {
+  strview_t view = strview_from_cstr("12345");
+  error_t   err  = strview_to_int64(&view, null);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+}
+
+/* -------------------------------------------------------------------------
+ * strview_to_double()
+ * ---------------------------------------------------------------------- */
+
+MICROTEST(strview_to_double, positive_decimal_succeeds) {
+  strview_t        view = strview_from_cstr("3.14");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_TRUE(out > 3.139 && out < 3.141);
+}
+
+MICROTEST(strview_to_double, negative_decimal_succeeds) {
+  strview_t        view = strview_from_cstr("-2.5");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_TRUE(out > -2.501 && out < -2.499);
+}
+
+MICROTEST(strview_to_double, integer_like_value_succeeds) {
+  strview_t        view = strview_from_cstr("42");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_TRUE(out > 41.999 && out < 42.001);
+}
+
+MICROTEST(strview_to_double, succeeds_on_subview_not_ending_at_buffer_end) {
+  malunal_cstr_t   data = "3.14 and then some trailing text";
+  strview_t        view = strview(data, 4);
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+  MICROTEST_EXPECT_TRUE(out > 3.139 && out < 3.141);
+}
+
+MICROTEST(strview_to_double, trailing_garbage_reports_unconsumed) {
+  strview_t        view = strview_from_cstr("3.14xyz");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_double, non_numeric_reports_unconsumed) {
+  strview_t        view = strview_from_cstr("abc");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_double, empty_view_reports_unconsumed) {
+  strview_t        view = strview_from_cstr("");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_UNCONSUMED);
+}
+
+MICROTEST(strview_to_double, null_self_reports_null_input) {
+  malunal_double_t out = 99.0;
+  error_t          err = strview_to_double(null, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_NULL_INPUT);
+  MICROTEST_EXPECT_TRUE(out == 0.0);
+}
+
+MICROTEST(strview_to_double, overflow_reports_out_of_range) {
+  strview_t        view = strview_from_cstr("1e400");
+  malunal_double_t out  = 0.0;
+  error_t          err  = strview_to_double(&view, &out);
+
+  MICROTEST_EXPECT_NOT_NULL(err.domain);
+  MICROTEST_EXPECT_EQ(err.code, (malunal_int32_t)STRVIEW_ERROR_OUT_OF_RANGE);
+}
+
+MICROTEST(strview_to_double, null_out_pointer_does_not_crash) {
+  strview_t view = strview_from_cstr("3.14");
+  error_t   err  = strview_to_double(&view, null);
+
+  MICROTEST_EXPECT_NULL(err.domain);
+}
+
 /* -------------------------------------------------------------------------
  * STRVIEW_NPOS
  * ---------------------------------------------------------------------- */
@@ -375,4 +570,3 @@ MICROTEST(strview_npos, is_max_size_value) {
 }
 
 MICROTEST_MAIN()
-