Added implementations from pdcore

[pdutils] / utils / comm / comm.c

diff --git a/utils/comm/comm.c b/utils/comm/comm.c
new file mode 100644 (file)
index 0000000..72aba31
--- /dev/null
+++ b/utils/comm/comm.c
@@ -0,0 +1,252 @@
+/*
+ * comm.c - select or reject lines common to two files
+ *
+ * Version: 2008-1.01
+ * Build:   c89 -o comm comm.c
+ * Source:  <http://pdcore.sourceforge.net/>
+ * Spec:    <http://www.opengroup.org/onlinepubs/9699919799/utilities/comm.html>
+ *
+ * This is free and unencumbered software released into the public domain,
+ * provided "as is", without warranty of any kind, express or implied. See the
+ * file UNLICENSE and the website <http://unlicense.org> for further details.
+ */
+
+
+#define _POSIX_SOURCE
+
+#include <errno.h>
+#include <fcntl.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define USAGE     "usage: comm [-123] file1 file2\n"
+#define ENOMALLOC "Unable to allocate memory for read buffer"
+#define BUFSIZE   4096
+#define LINESIZE  64
+#define SYSERR    1
+#define APPERR    0
+
+typedef struct { int     fd;
+                 char   *fn;
+                 int     eof;
+                 char    buf[BUFSIZE];
+                 size_t  bufpos;
+                 size_t  eobuf;
+                 char   *line;
+                 size_t  linesz;
+               } FINFO;
+
+static void initfile(FINFO *file, char *fn);
+static void cleanup(FINFO *file);
+static void commfiles(FINFO *file1, FINFO *file2);
+static int getline(FINFO *file);
+static void fillbuf(FINFO *file);
+static void fatal(int errtype, char *s);
+
+static int opt1, opt2, opt3;
+
+
+int main(int argc, char **argv)
+{
+    extern int optind, opterr;
+    int c;
+    FINFO file1, file2;
+
+    setlocale(LC_ALL, "");
+    opterr = 0;
+
+    while ((c = getopt(argc, argv, "123")) != -1)
+        switch (c)
+        {
+        case '1':
+            opt1 = 1;
+            break;
+        case '2':
+            opt2 = 1;
+            break;
+        case '3':
+            opt3 = 1;
+            break;
+        default:
+            fprintf(stderr, USAGE);
+            exit(1);
+        }
+
+    argc -= optind;
+    argv += optind;
+
+    if (argc != 2)
+        fatal(APPERR, USAGE);
+
+    initfile(&file1, argv[0]);
+    initfile(&file2, argv[1]);
+
+    commfiles(&file1, &file2);
+
+    cleanup(&file1);
+    cleanup(&file2);
+
+    return(0);
+}
+
+
+void initfile(FINFO *file, char *fn)
+{
+    int fd;
+
+    if (strcmp(fn, "-") == 0)
+        fd = STDIN_FILENO;
+    else
+        if ((fd = open(fn, O_RDONLY)) == -1)
+            fatal(SYSERR, fn);
+
+    file->fd     = fd;
+    file->fn     = fn;
+    file->eof    = 0;
+    file->bufpos = 0;
+    file->eobuf  = 0;
+    file->linesz = LINESIZE;
+
+    if ((file->line = malloc(file->linesz)) == NULL)
+        fatal(APPERR, ENOMALLOC);
+}
+
+
+void cleanup(FINFO *file)
+{
+    free(file->line);
+
+    if (strcmp(file->fn, "-") != 0 && close(file->fd) == -1)
+        fatal(SYSERR, file->fn);
+}
+
+
+void commfiles(FINFO *file1, FINFO *file2)
+{
+    int cmp;
+
+    if (getline(file1) && getline(file2))
+        while(1)
+        {
+            cmp = strcoll(file1->line, file2->line);
+
+            if (cmp == 0)
+            {
+                if (! opt3)
+                    printf("%s%s%s\n", (opt1 ? "" : "\t"), (opt2 ? "" : "\t"), file1->line);
+
+                if ((getline(file1) + getline(file2)) < 2)
+                    break;
+            }
+
+            else if (cmp > 0)
+            {
+                if (! opt2)
+                    printf("%s%s\n", (opt1 ? "" : "\t"), file2->line);
+
+                if (! getline(file2))
+                    break;
+            }
+
+            else   /* cmp < 0 */
+            {
+                if (! opt1)
+                    printf("%s\n", file1->line);
+
+                if (! getline(file1))
+                    break;
+            }
+        }
+
+    while(! file1->eof && ! opt1)
+    {
+        printf("%s\n", file1->line);
+        getline(file1);
+    }
+
+    while(! file2->eof && ! opt2)
+    {
+        printf("%s%s\n", (opt1 ? "" : "\t"), file2->line);
+        getline(file2);
+    }
+}
+
+
+int getline(FINFO *file)
+{
+    int success = 0;
+    size_t i = 0;
+
+    if (! file->eof)
+    {
+        while(1)
+        {
+            if (i == file->linesz)
+            {
+                file->linesz = file->linesz + LINESIZE;
+                if ((file->line = realloc(file->line, file->linesz)) == NULL)
+                    fatal(APPERR, ENOMALLOC);
+            }
+
+            if (file->bufpos >= file->eobuf)
+            {
+                fillbuf(file);
+                if (file->eof)
+                {
+                    if (i > 0)
+                    {
+                        file->line[i] = '\0';
+                        success = 1;
+                    }
+                    break;
+                }
+            }
+
+            if (file->buf[file->bufpos] == '\n')
+            {
+                file->bufpos++;
+                file->line[i] = '\0';
+                success = 1;
+                break;
+            }
+            else
+                file->line[i++] = file->buf[file->bufpos++];
+        }
+    }
+
+    return(success);
+}
+
+
+void fillbuf(FINFO *file)
+{
+    ssize_t n;
+
+    if (! file->eof)
+    {
+        if ((n = read(file->fd, file->buf, BUFSIZE)) < 0)
+            fatal(SYSERR, file->fn);
+
+        if (n == 0)
+            file->eof = 1;
+        else
+        {
+            file->bufpos = 0;
+            file->eobuf  = n;
+        }
+    }
+}
+
+
+void fatal(int errtype, char *s)
+{
+    if (errtype == SYSERR)
+        fprintf(stderr, "comm: %s: %s\n", s, strerror(errno));
+    else
+        fprintf(stderr, "comm: %s\n", s);
+
+    exit(1);
+}