Be ever so pedantic about escaping chars that the shell might not like...

diff --git a/findutils/xargs.c b/findutils/xargs.c
index 478e0ee6d630549a3f1727c8de3c240b1a77da1f..21bfb6bbee5ca6e0b3da66118cdebeb36801b533 100644 (file)
--- a/findutils/xargs.c
+++ b/findutils/xargs.c
@@ -29,6 +29,59 @@
 #include <getopt.h>
 #include <ctype.h>
 
+/* get_sh_safe_line_from_file() - This function reads an entire line from a text file
+ * up to a newline. It returns a malloc'ed char * which must be stored and
+ * free'ed  by the caller. */
+extern char *get_sh_safe_line_from_file(FILE *file)
+{
+       static const int GROWBY = 80; /* how large we will grow strings by */
+
+       char ch, last_ch = 0;
+       char tmp[]=" ";
+       int idx = 0;
+       char *linebuf = NULL;
+       int linebufsz = 0;
+
+       while (1) {
+               ch = fgetc(file);
+               if (ch == EOF)
+                       break;
+               
+               /* grow the line buffer as necessary */
+               while (idx > linebufsz-4)
+                       linebuf = xrealloc(linebuf, linebufsz += GROWBY);
+
+               /* Remove any extra spaces */
+               if (last_ch == ' ' && ch == ' ')
+                       continue;
+
+               /* Replace any tabs with spaces */
+               if (ch == '\t')
+                       ch=' ';
+
+               /* Escape any characters that are treated specially by /bin/sh */
+               *tmp=ch;
+               if (strpbrk(tmp, "\\~`!$^&*()=|{}[];\"'<>?#") != NULL && last_ch!='\\') {
+                       linebuf[idx++] = '\\';
+               }
+
+               linebuf[idx++] = ch;
+               last_ch=ch;
+
+               if (ch == '\n')
+                       break;
+       }
+       if (idx == 0 && last_ch!=0)
+               linebuf[idx++]=' ';
+
+       if (idx == 0)
+               return NULL;
+
+       linebuf[idx] = 0;
+       return linebuf;
+}
+
+
 
 int xargs_main(int argc, char **argv)
 {
@@ -54,7 +107,7 @@ int xargs_main(int argc, char **argv)
        }
 
        /* Store the command and arguments to be executed (from the command line) */
-       if (argc == 1) {
+       if (argc == 0) {
                len_args_from_cmdline = 6;
                args_from_cmdline = xmalloc(len_args_from_cmdline);
                strcat(args_from_cmdline, "echo ");
@@ -72,6 +125,7 @@ int xargs_main(int argc, char **argv)
                        }
                        strcat(args_from_cmdline, *argv);
                        strcat(args_from_cmdline, " ");
+                       ++argv;
                }
        }
 
@@ -79,30 +133,19 @@ int xargs_main(int argc, char **argv)
        len_cmd_to_be_executed=10;
        cmd_to_be_executed = xcalloc(len_cmd_to_be_executed, sizeof(char));
        strcpy(cmd_to_be_executed, args_from_cmdline);
-       strcat(cmd_to_be_executed, " \"");
 
        /* Now, read in one line at a time from stdin, and run command+args on it */
-       in_from_stdin = get_line_from_file(stdin);
+       in_from_stdin = get_sh_safe_line_from_file(stdin);
        for (;in_from_stdin!=NULL;) {
                char *tmp;
                opt = strlen(in_from_stdin);
                len = opt + len_args_from_cmdline;
                len_cmd_to_be_executed+=len+3;
                cmd_to_be_executed=xrealloc(cmd_to_be_executed, len_cmd_to_be_executed);
-                       
+
                /* Strip out the final \n */
                in_from_stdin[opt-1]=' ';
-               
-               /* Replace any tabs with spaces */
-               while( (tmp = strchr(in_from_stdin, '\t')) != NULL )
-                       *tmp=' ';
-
-               /* Strip out any extra intra-word spaces */
-               while( (tmp = strstr(in_from_stdin, "  ")) != NULL ) {
-                       opt = strlen(in_from_stdin);
-                       memmove(tmp, tmp+1, opt-(tmp-in_from_stdin));
-               }
-
+                       
                /* trim trailing whitespace */
                opt = strlen(in_from_stdin) - 1;
                while (isspace(in_from_stdin[opt]))
@@ -118,10 +161,9 @@ int xargs_main(int argc, char **argv)
                strcat(cmd_to_be_executed, " ");
        
                free(in_from_stdin);
-               in_from_stdin = get_line_from_file(stdin);
+               in_from_stdin = get_sh_safe_line_from_file(stdin);
        }
 
-       strcat(cmd_to_be_executed, "\"");
        if (traceflag==1)
                fputs(cmd_to_be_executed, stderr);
 

diff --git a/xargs.c b/xargs.c
index 478e0ee6d630549a3f1727c8de3c240b1a77da1f..21bfb6bbee5ca6e0b3da66118cdebeb36801b533 100644 (file)
--- a/xargs.c
+++ b/xargs.c
@@ -29,6 +29,59 @@
 #include <getopt.h>
 #include <ctype.h>
 
+/* get_sh_safe_line_from_file() - This function reads an entire line from a text file
+ * up to a newline. It returns a malloc'ed char * which must be stored and
+ * free'ed  by the caller. */
+extern char *get_sh_safe_line_from_file(FILE *file)
+{
+       static const int GROWBY = 80; /* how large we will grow strings by */
+
+       char ch, last_ch = 0;
+       char tmp[]=" ";
+       int idx = 0;
+       char *linebuf = NULL;
+       int linebufsz = 0;
+
+       while (1) {
+               ch = fgetc(file);
+               if (ch == EOF)
+                       break;
+               
+               /* grow the line buffer as necessary */
+               while (idx > linebufsz-4)
+                       linebuf = xrealloc(linebuf, linebufsz += GROWBY);
+
+               /* Remove any extra spaces */
+               if (last_ch == ' ' && ch == ' ')
+                       continue;
+
+               /* Replace any tabs with spaces */
+               if (ch == '\t')
+                       ch=' ';
+
+               /* Escape any characters that are treated specially by /bin/sh */
+               *tmp=ch;
+               if (strpbrk(tmp, "\\~`!$^&*()=|{}[];\"'<>?#") != NULL && last_ch!='\\') {
+                       linebuf[idx++] = '\\';
+               }
+
+               linebuf[idx++] = ch;
+               last_ch=ch;
+
+               if (ch == '\n')
+                       break;
+       }
+       if (idx == 0 && last_ch!=0)
+               linebuf[idx++]=' ';
+
+       if (idx == 0)
+               return NULL;
+
+       linebuf[idx] = 0;
+       return linebuf;
+}
+
+
 
 int xargs_main(int argc, char **argv)
 {
@@ -54,7 +107,7 @@ int xargs_main(int argc, char **argv)
        }
 
        /* Store the command and arguments to be executed (from the command line) */
-       if (argc == 1) {
+       if (argc == 0) {
                len_args_from_cmdline = 6;
                args_from_cmdline = xmalloc(len_args_from_cmdline);
                strcat(args_from_cmdline, "echo ");
@@ -72,6 +125,7 @@ int xargs_main(int argc, char **argv)
                        }
                        strcat(args_from_cmdline, *argv);
                        strcat(args_from_cmdline, " ");
+                       ++argv;
                }
        }
 
@@ -79,30 +133,19 @@ int xargs_main(int argc, char **argv)
        len_cmd_to_be_executed=10;
        cmd_to_be_executed = xcalloc(len_cmd_to_be_executed, sizeof(char));
        strcpy(cmd_to_be_executed, args_from_cmdline);
-       strcat(cmd_to_be_executed, " \"");
 
        /* Now, read in one line at a time from stdin, and run command+args on it */
-       in_from_stdin = get_line_from_file(stdin);
+       in_from_stdin = get_sh_safe_line_from_file(stdin);
        for (;in_from_stdin!=NULL;) {
                char *tmp;
                opt = strlen(in_from_stdin);
                len = opt + len_args_from_cmdline;
                len_cmd_to_be_executed+=len+3;
                cmd_to_be_executed=xrealloc(cmd_to_be_executed, len_cmd_to_be_executed);
-                       
+
                /* Strip out the final \n */
                in_from_stdin[opt-1]=' ';
-               
-               /* Replace any tabs with spaces */
-               while( (tmp = strchr(in_from_stdin, '\t')) != NULL )
-                       *tmp=' ';
-
-               /* Strip out any extra intra-word spaces */
-               while( (tmp = strstr(in_from_stdin, "  ")) != NULL ) {
-                       opt = strlen(in_from_stdin);
-                       memmove(tmp, tmp+1, opt-(tmp-in_from_stdin));
-               }
-
+                       
                /* trim trailing whitespace */
                opt = strlen(in_from_stdin) - 1;
                while (isspace(in_from_stdin[opt]))
@@ -118,10 +161,9 @@ int xargs_main(int argc, char **argv)
                strcat(cmd_to_be_executed, " ");
        
                free(in_from_stdin);
-               in_from_stdin = get_line_from_file(stdin);
+               in_from_stdin = get_sh_safe_line_from_file(stdin);
        }
 
-       strcat(cmd_to_be_executed, "\"");
        if (traceflag==1)
                fputs(cmd_to_be_executed, stderr);