Andrew's git - gitweb.git/blob - builtin-stripspace.c

   1#include "builtin.h"
   2#include "cache.h"
   3
   4/*
   5 * Remove trailing spaces from a line.
   6 *
   7 * If the line ends with newline, it will be removed too.
   8 * Returns the new length of the string.
   9 */
  10static int cleanup(char *line, int len)
  11{
  12        if (len) {
  13                if (line[len - 1] == '\n')
  14                        len--;
  15
  16                while (len) {
  17                        unsigned char c = line[len - 1];
  18                        if (!isspace(c))
  19                                break;
  20                        len--;
  21                }
  22                line[len] = 0;
  23        }
  24        return len;
  25}
  26
  27/*
  28 * Remove empty lines from the beginning and end
  29 * and also trailing spaces from every line.
  30 *
  31 * Turn multiple consecutive empty lines between paragraphs
  32 * into just one empty line.
  33 *
  34 * If the input has only empty lines and spaces,
  35 * no output will be produced.
  36 *
  37 * Enable skip_comments to skip every line starting with "#".
  38 */
  39void stripspace(FILE *in, FILE *out, int skip_comments)
  40{
  41        int empties = -1;
  42        int alloc = 1024;
  43        char *line = xmalloc(alloc);
  44
  45        while (fgets(line, alloc, in)) {
  46                int len = strlen(line);
  47
  48                while (len == alloc - 1 && line[len - 1] != '\n') {
  49                        alloc = alloc_nr(alloc);
  50                        line = xrealloc(line, alloc);
  51                        fgets(line + len, alloc - len, in);
  52                        len += strlen(line + len);
  53                }
  54
  55                if (skip_comments && line[0] == '#')
  56                        continue;
  57                len = cleanup(line, len);
  58
  59                /* Not just an empty line? */
  60                if (len) {
  61                        if (empties > 0)
  62                                fputc('\n', out);
  63                        empties = 0;
  64                        fputs(line, out);
  65                        fputc('\n', out);
  66                        continue;
  67                }
  68                if (empties < 0)
  69                        continue;
  70                empties++;
  71        }
  72        free(line);
  73}
  74
  75int cmd_stripspace(int argc, const char **argv, const char *prefix)
  76{
  77        stripspace(stdin, stdout, 0);
  78        return 0;
  79}