Diff: string_tokenizer.c

Revision:

0:fa2de1b79154

Child:

1:9190c0f4d23a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/string_tokenizer.c	Fri Apr 08 12:01:36 2016 -0700
@@ -0,0 +1,210 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+//
+// PUT NO INCLUDES BEFORE HERE
+//
+#ifdef _CRTDBG_MAP_ALLOC
+#include <crtdbg.h>
+#endif
+#include "azure_c_shared_utility/gballoc.h"
+
+//
+// PUT NO CLIENT LIBRARY INCLUDES BEFORE HERE
+//
+
+#include <stdbool.h>
+#include "azure_c_shared_utility/string_tokenizer.h"
+#include "azure_c_shared_utility/iot_logging.h"
+#include "azure_c_shared_utility/crt_abstractions.h"
+
+typedef struct STRING_TOKEN_TAG
+{
+    const char* inputString;
+    const char* currentPos;
+    size_t sizeOfinputString;
+} STRING_TOKEN;
+
+STRING_TOKENIZER_HANDLE STRING_TOKENIZER_create(STRING_HANDLE handle)
+{
+    STRING_TOKENIZER_HANDLE result;
+
+    /* Codes_SRS_STRING_04_001: [STRING_TOKENIZER_create shall return an NULL STRING_TOKENIZER_HANDLE if parameter handle is NULL] */
+    if (handle == NULL)
+    {
+        LogError("Invalid Argument. Handle cannot be NULL.\r\n");
+        result = NULL;
+    }
+    else
+    {
+        /* Codes_SRS_STRING_04_002: [STRING_TOKENIZER_create shall allocate a new STRING_TOKENIZER_HANDLE having the content of the STRING_HANDLE copied and current position pointing at the beginning of the string] */
+        result = STRING_TOKENIZER_create_from_char(STRING_c_str(handle));
+    }
+
+    return result;
+}
+
+extern STRING_TOKENIZER_HANDLE STRING_TOKENIZER_create_from_char(const char* input)
+{
+    STRING_TOKEN *result;
+    char* inputStringToMalloc;
+
+    /* Codes_SRS_STRING_07_001: [STRING_TOKENIZER_create shall return an NULL STRING_TOKENIZER_HANDLE if parameter input is NULL] */
+    if (input == NULL)
+    {
+        LogError("Invalid Argument. Handle cannot be NULL.\r\n");
+        result = NULL;
+    }
+    /* Codes_SRS_STRING_07_002: [STRING_TOKENIZER_create shall allocate a new STRING_TOKENIZER_HANDLE having the content of the STRING_HANDLE copied and current position pointing at the beginning of the string] */
+    else if ((result = (STRING_TOKEN*)malloc(sizeof(STRING_TOKEN))) == NULL)
+    {
+        LogError("Memory Allocation failed. Cannot allocate STRING_TOKENIZER.\r\n");
+    }
+    else if ((mallocAndStrcpy_s(&inputStringToMalloc, input)) != 0)
+    {
+        LogError("Memory Allocation Failed. Cannot allocate and copy string Content.\r\n");
+        free(result);
+        result = NULL;
+    }
+    else
+    {
+        result->inputString = inputStringToMalloc;
+        result->currentPos = result->inputString; //Current Pos will point to the initial position of Token.
+        result->sizeOfinputString = strlen(result->inputString); //Calculate Size of Current String
+    }
+    return (STRING_TOKENIZER_HANDLE)result;
+}
+
+int STRING_TOKENIZER_get_next_token(STRING_TOKENIZER_HANDLE tokenizer, STRING_HANDLE output, const char* delimiters)
+{
+    int result;
+    /* Codes_SRS_STRING_04_004: [STRING_TOKENIZER_get_next_token shall return a nonzero value if any of the 3 parameters is NULL] */
+    if (tokenizer == NULL || output == NULL || delimiters == NULL)
+    {
+        result = __LINE__;
+    }
+    else 
+    {
+        STRING_TOKEN* token = (STRING_TOKEN*)tokenizer;
+        /* Codes_SRS_STRING_04_011: [Each subsequent call to STRING_TOKENIZER_get_next_token starts searching from the saved position on t and behaves as described above.] */
+        size_t remainingInputStringSize = token->sizeOfinputString - (token->currentPos - token->inputString);
+        size_t delimitterSize = strlen(delimiters);
+
+        /* First Check if we reached the end of the string*/
+        /* Codes_SRS_STRING_TOKENIZER_04_014: [STRING_TOKENIZER_get_next_token shall return nonzero value if t contains an empty string.] */
+        if (remainingInputStringSize == 0)
+        {
+            result = __LINE__;
+        }
+        else if (delimitterSize == 0)
+        {
+            LogError("Empty delimiters parameter.\r\n");
+            result = __LINE__;
+        }
+        else
+        {
+            size_t i;
+            size_t j;
+            /* Codes_SRS_STRING_04_005: [STRING_TOKENIZER_get_next_token searches the string inside STRING_TOKENIZER_HANDLE for the first character that is NOT contained in the current delimiter] */
+            for (i = 0; i < remainingInputStringSize; i++)
+            {
+                bool foundDelimitter = false;
+                for (j = 0; j < delimitterSize; j++)
+                {
+                    if (token->currentPos[i] == delimiters[j])
+                    {
+                        foundDelimitter = true;
+                        break;
+                    }
+                }
+
+                /* Codes_SRS_STRING_04_007: [If such a character is found, STRING_TOKENIZER_get_next_token consider it as the start of a token.] */
+                if (!foundDelimitter)
+                {
+                    break;
+                }
+            }
+
+            /* Codes_SRS_STRING_04_006: [If no such character is found, then STRING_TOKENIZER_get_next_token shall return a nonzero Value (You've reach the end of the string or the string consists with only delimiters).] */
+            //At this point update Current Pos to the character of the last token found or end of String.
+            token->currentPos += i; 
+            
+            //Update the remainingInputStringSize
+            remainingInputStringSize -= i;
+            
+            /* Codes_SRS_STRING_04_006: [If no such character is found, then STRING_TOKENIZER_get_next_token shall return a nonzero Value (You've reach the end of the string or the string consists with only delimiters).] */
+            if (remainingInputStringSize == 0)
+            {
+                result = __LINE__;
+            }
+            else
+            {
+                bool foundDelimitter = false;
+                char* endOfTokenPosition=NULL;
+                size_t amountOfCharactersToCopy;
+                size_t j;
+                //At this point the Current Pos is pointing to a character that is point to a nonDelimiter. So, now search for a Delimiter, till the end of the String. 
+                /*Codes_SRS_STRING_04_008: [STRING_TOKENIZER_get_next_token than searches from the start of a token for a character that is contained in the delimiters string.] */
+                /* Codes_SRS_STRING_04_009: [If no such character is found, STRING_TOKENIZER_get_next_token extends the current token to the end of the string inside t, copies the token to output and returns 0.] */
+                /* Codes_SRS_STRING_04_010: [If such a character is found, STRING_TOKENIZER_get_next_token consider it the end of the token and copy it's content to output, updates the current position inside t to the next character and returns 0.] */
+                for (j = 0; j < delimitterSize; j++)
+                {
+                    if ((endOfTokenPosition = strchr(token->currentPos, delimiters[j])) != NULL)
+                    {
+                        foundDelimitter = true;
+                        break;
+                    }
+                }
+
+                //If token not found, than update the EndOfToken to the end of the inputString;
+                if (endOfTokenPosition == NULL)
+                {
+                    amountOfCharactersToCopy = remainingInputStringSize;
+                }
+                else
+                {
+                    amountOfCharactersToCopy = endOfTokenPosition - token->currentPos;
+                }
+                
+                //copy here the string to output. 
+                if (STRING_copy_n(output, token->currentPos, amountOfCharactersToCopy) != 0)
+                {
+                    LogError("Problem copying token to output String.\r\n");
+                    result = __LINE__;
+                }
+                else
+                {
+                    //Update the Current position.
+                    //Check if end of String reached so, currentPos points to the end of String.
+                    if (foundDelimitter)
+                    {
+                        token->currentPos += amountOfCharactersToCopy + 1;
+                    }
+                    else
+                    {
+                        token->currentPos += amountOfCharactersToCopy;
+                    }
+                    
+                    result = 0; //Result will be on the output. 
+                }
+            }
+        }
+    }
+
+    return result;
+}
+
+
+/* Codes_SRS_STRING_TOKENIZER_04_012: [STRING_TOKENIZER_destroy shall free the memory allocated by the STRING_TOKENIZER_create ] */
+void STRING_TOKENIZER_destroy(STRING_TOKENIZER_HANDLE t)
+{
+    /* Codes_SRS_STRING_TOKENIZER_04_013: [When the t argument is NULL, then STRING_TOKENIZER_destroy shall not attempt to free] */
+    if (t != NULL)
+    {
+        STRING_TOKEN* value = (STRING_TOKEN*)t;
+        free((char*)value->inputString);
+        value->inputString = NULL;
+        free(value);
+    }
+}
+