Implementation of getdelim












0












$begingroup$


Note: I wasn't trying to follow the existing getdelim signature exactly. I needed to add the consume argument for a project I'm working on.



I am pretty new to writing c. It would be great to get some feedback on whether best practices are being followed.



Some things I learned about while writing this code (which might be areas that need improvement)




  • Pointer arithmetic


  • FILE * error handling


ssize_t read_until_deliminator(char **buffer, size_t *size, char deliminator, 
FILE *file, bool consume)
{
char ch;
char *buffer_pos;

if (buffer == NULL || size == NULL || ferror(file)) {
errno = EINVAL;
return -1;
}

if (buffer == NULL || *size == 0) {
// Empty buffer supplied
*size = 128;
*buffer = malloc(*size);

if (*buffer == NULL) {
errno = ENOMEM;
return -1;
}
}

buffer_pos = *buffer;

for (;;) {
ch = getc(file);

if (ch == EOF) {
break;
}

if ((buffer_pos + 1) == (*buffer + *size)) {
// No more room in buffer
size_t new_size = *size * 2;
char* realloc_buffer = realloc(*buffer, new_size);

if (realloc_buffer == NULL) {
errno = ENOMEM;
return -1;
}

buffer_pos = realloc_buffer + (buffer_pos - *buffer);
*buffer = realloc_buffer;
*size = new_size;
}

*buffer_pos++ = ch;

if (ch == deliminator) {
if (!consume) {
// If not consuming delim roll back buffer
*buffer_pos--;
}

break;
}
}

if (ch == EOF && buffer_pos == *buffer) {
return -1;
}

*buffer_pos = '';

return buffer_pos - *buffer;
}


Minimal working example: https://repl.it/repls/SlimEarlyField



Thank you to anyone who look over this and gives me feedback. I don't really know anyone who works professionally in C so this is a rare opportunity for me to get valuable feedback, and improve my skills.









share







New contributor




Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$

















    0












    $begingroup$


    Note: I wasn't trying to follow the existing getdelim signature exactly. I needed to add the consume argument for a project I'm working on.



    I am pretty new to writing c. It would be great to get some feedback on whether best practices are being followed.



    Some things I learned about while writing this code (which might be areas that need improvement)




    • Pointer arithmetic


    • FILE * error handling


    ssize_t read_until_deliminator(char **buffer, size_t *size, char deliminator, 
    FILE *file, bool consume)
    {
    char ch;
    char *buffer_pos;

    if (buffer == NULL || size == NULL || ferror(file)) {
    errno = EINVAL;
    return -1;
    }

    if (buffer == NULL || *size == 0) {
    // Empty buffer supplied
    *size = 128;
    *buffer = malloc(*size);

    if (*buffer == NULL) {
    errno = ENOMEM;
    return -1;
    }
    }

    buffer_pos = *buffer;

    for (;;) {
    ch = getc(file);

    if (ch == EOF) {
    break;
    }

    if ((buffer_pos + 1) == (*buffer + *size)) {
    // No more room in buffer
    size_t new_size = *size * 2;
    char* realloc_buffer = realloc(*buffer, new_size);

    if (realloc_buffer == NULL) {
    errno = ENOMEM;
    return -1;
    }

    buffer_pos = realloc_buffer + (buffer_pos - *buffer);
    *buffer = realloc_buffer;
    *size = new_size;
    }

    *buffer_pos++ = ch;

    if (ch == deliminator) {
    if (!consume) {
    // If not consuming delim roll back buffer
    *buffer_pos--;
    }

    break;
    }
    }

    if (ch == EOF && buffer_pos == *buffer) {
    return -1;
    }

    *buffer_pos = '';

    return buffer_pos - *buffer;
    }


    Minimal working example: https://repl.it/repls/SlimEarlyField



    Thank you to anyone who look over this and gives me feedback. I don't really know anyone who works professionally in C so this is a rare opportunity for me to get valuable feedback, and improve my skills.









    share







    New contributor




    Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.







    $endgroup$















      0












      0








      0





      $begingroup$


      Note: I wasn't trying to follow the existing getdelim signature exactly. I needed to add the consume argument for a project I'm working on.



      I am pretty new to writing c. It would be great to get some feedback on whether best practices are being followed.



      Some things I learned about while writing this code (which might be areas that need improvement)




      • Pointer arithmetic


      • FILE * error handling


      ssize_t read_until_deliminator(char **buffer, size_t *size, char deliminator, 
      FILE *file, bool consume)
      {
      char ch;
      char *buffer_pos;

      if (buffer == NULL || size == NULL || ferror(file)) {
      errno = EINVAL;
      return -1;
      }

      if (buffer == NULL || *size == 0) {
      // Empty buffer supplied
      *size = 128;
      *buffer = malloc(*size);

      if (*buffer == NULL) {
      errno = ENOMEM;
      return -1;
      }
      }

      buffer_pos = *buffer;

      for (;;) {
      ch = getc(file);

      if (ch == EOF) {
      break;
      }

      if ((buffer_pos + 1) == (*buffer + *size)) {
      // No more room in buffer
      size_t new_size = *size * 2;
      char* realloc_buffer = realloc(*buffer, new_size);

      if (realloc_buffer == NULL) {
      errno = ENOMEM;
      return -1;
      }

      buffer_pos = realloc_buffer + (buffer_pos - *buffer);
      *buffer = realloc_buffer;
      *size = new_size;
      }

      *buffer_pos++ = ch;

      if (ch == deliminator) {
      if (!consume) {
      // If not consuming delim roll back buffer
      *buffer_pos--;
      }

      break;
      }
      }

      if (ch == EOF && buffer_pos == *buffer) {
      return -1;
      }

      *buffer_pos = '';

      return buffer_pos - *buffer;
      }


      Minimal working example: https://repl.it/repls/SlimEarlyField



      Thank you to anyone who look over this and gives me feedback. I don't really know anyone who works professionally in C so this is a rare opportunity for me to get valuable feedback, and improve my skills.









      share







      New contributor




      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.







      $endgroup$




      Note: I wasn't trying to follow the existing getdelim signature exactly. I needed to add the consume argument for a project I'm working on.



      I am pretty new to writing c. It would be great to get some feedback on whether best practices are being followed.



      Some things I learned about while writing this code (which might be areas that need improvement)




      • Pointer arithmetic


      • FILE * error handling


      ssize_t read_until_deliminator(char **buffer, size_t *size, char deliminator, 
      FILE *file, bool consume)
      {
      char ch;
      char *buffer_pos;

      if (buffer == NULL || size == NULL || ferror(file)) {
      errno = EINVAL;
      return -1;
      }

      if (buffer == NULL || *size == 0) {
      // Empty buffer supplied
      *size = 128;
      *buffer = malloc(*size);

      if (*buffer == NULL) {
      errno = ENOMEM;
      return -1;
      }
      }

      buffer_pos = *buffer;

      for (;;) {
      ch = getc(file);

      if (ch == EOF) {
      break;
      }

      if ((buffer_pos + 1) == (*buffer + *size)) {
      // No more room in buffer
      size_t new_size = *size * 2;
      char* realloc_buffer = realloc(*buffer, new_size);

      if (realloc_buffer == NULL) {
      errno = ENOMEM;
      return -1;
      }

      buffer_pos = realloc_buffer + (buffer_pos - *buffer);
      *buffer = realloc_buffer;
      *size = new_size;
      }

      *buffer_pos++ = ch;

      if (ch == deliminator) {
      if (!consume) {
      // If not consuming delim roll back buffer
      *buffer_pos--;
      }

      break;
      }
      }

      if (ch == EOF && buffer_pos == *buffer) {
      return -1;
      }

      *buffer_pos = '';

      return buffer_pos - *buffer;
      }


      Minimal working example: https://repl.it/repls/SlimEarlyField



      Thank you to anyone who look over this and gives me feedback. I don't really know anyone who works professionally in C so this is a rare opportunity for me to get valuable feedback, and improve my skills.







      c





      share







      New contributor




      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.










      share







      New contributor




      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.








      share



      share






      New contributor




      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 8 mins ago









      Chris FrankChris Frank

      1011




      1011




      New contributor




      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      Chris Frank is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          0






          active

          oldest

          votes











          Your Answer





          StackExchange.ifUsing("editor", function () {
          return StackExchange.using("mathjaxEditing", function () {
          StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
          StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["\$", "\$"]]);
          });
          });
          }, "mathjax-editing");

          StackExchange.ifUsing("editor", function () {
          StackExchange.using("externalEditor", function () {
          StackExchange.using("snippets", function () {
          StackExchange.snippets.init();
          });
          });
          }, "code-snippets");

          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "196"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: false,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: null,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });






          Chris Frank is a new contributor. Be nice, and check out our Code of Conduct.










          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodereview.stackexchange.com%2fquestions%2f211663%2fimplementation-of-getdelim%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          0






          active

          oldest

          votes








          0






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes








          Chris Frank is a new contributor. Be nice, and check out our Code of Conduct.










          draft saved

          draft discarded


















          Chris Frank is a new contributor. Be nice, and check out our Code of Conduct.













          Chris Frank is a new contributor. Be nice, and check out our Code of Conduct.












          Chris Frank is a new contributor. Be nice, and check out our Code of Conduct.
















          Thanks for contributing an answer to Code Review Stack Exchange!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          Use MathJax to format equations. MathJax reference.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodereview.stackexchange.com%2fquestions%2f211663%2fimplementation-of-getdelim%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          404 Error Contact Form 7 ajax form submitting

          How to know if a Active Directory user can login interactively

          Refactoring coordinates for Minecraft Pi buildings written in Python