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authorFederico Ceratto <federico.ceratto@gmail.com>2016-03-30 21:40:42 +0000
committerFederico Ceratto <federico.ceratto@gmail.com>2016-03-30 21:40:42 +0000
commit9ce153ce7167c11adba8ac225edc7a707e97c6eb (patch)
tree9f6e849cce2dcc7e5b4e9e6252c843dc2d0787a2 /src/procfile.c
downloadnetdata-9ce153ce7167c11adba8ac225edc7a707e97c6eb.tar.xz
netdata-9ce153ce7167c11adba8ac225edc7a707e97c6eb.zip
Imported Upstream version 1.0.0upstream/1.0.0
Diffstat (limited to 'src/procfile.c')
-rwxr-xr-xsrc/procfile.c400
1 files changed, 400 insertions, 0 deletions
diff --git a/src/procfile.c b/src/procfile.c
new file mode 100755
index 000000000..7a4857959
--- /dev/null
+++ b/src/procfile.c
@@ -0,0 +1,400 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <malloc.h>
+#include <ctype.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#include "common.h"
+#include "log.h"
+#include "procfile.h"
+
+#define PF_PREFIX "PROCFILE"
+
+#define PFWORDS_INCREASE_STEP 200
+#define PFLINES_INCREASE_STEP 10
+#define PROCFILE_INCREMENT_BUFFER 512
+
+int procfile_adaptive_initial_allocation = 0;
+
+// if adaptive allocation is set, these store the
+// max values we have seen so far
+uint32_t procfile_max_lines = PFLINES_INCREASE_STEP;
+uint32_t procfile_max_words = PFWORDS_INCREASE_STEP;
+size_t procfile_max_allocation = PROCFILE_INCREMENT_BUFFER;
+
+// ----------------------------------------------------------------------------
+// An array of words
+
+
+pfwords *pfwords_add(pfwords *fw, char *str) {
+ // debug(D_PROCFILE, PF_PREFIX ": adding word No %d: '%s'", fw->len, str);
+
+ if(unlikely(fw->len == fw->size)) {
+ // debug(D_PROCFILE, PF_PREFIX ": expanding words");
+
+ pfwords *new = realloc(fw, sizeof(pfwords) + (fw->size + PFWORDS_INCREASE_STEP) * sizeof(char *));
+ if(unlikely(!new)) {
+ error(PF_PREFIX ": failed to expand words");
+ free(fw);
+ return NULL;
+ }
+ fw = new;
+ fw->size += PFWORDS_INCREASE_STEP;
+ }
+
+ fw->words[fw->len++] = str;
+
+ return fw;
+}
+
+pfwords *pfwords_new(void) {
+ // debug(D_PROCFILE, PF_PREFIX ": initializing words");
+
+ uint32_t size = (procfile_adaptive_initial_allocation) ? procfile_max_words : PFWORDS_INCREASE_STEP;
+
+ pfwords *new = malloc(sizeof(pfwords) + size * sizeof(char *));
+ if(unlikely(!new)) return NULL;
+
+ new->len = 0;
+ new->size = size;
+ return new;
+}
+
+void pfwords_reset(pfwords *fw) {
+ // debug(D_PROCFILE, PF_PREFIX ": reseting words");
+ fw->len = 0;
+}
+
+void pfwords_free(pfwords *fw) {
+ // debug(D_PROCFILE, PF_PREFIX ": freeing words");
+
+ free(fw);
+}
+
+
+// ----------------------------------------------------------------------------
+// An array of lines
+
+pflines *pflines_add(pflines *fl, uint32_t first_word) {
+ // debug(D_PROCFILE, PF_PREFIX ": adding line %d at word %d", fl->len, first_word);
+
+ if(unlikely(fl->len == fl->size)) {
+ // debug(D_PROCFILE, PF_PREFIX ": expanding lines");
+
+ pflines *new = realloc(fl, sizeof(pflines) + (fl->size + PFLINES_INCREASE_STEP) * sizeof(ffline));
+ if(unlikely(!new)) {
+ error(PF_PREFIX ": failed to expand lines");
+ free(fl);
+ return NULL;
+ }
+ fl = new;
+ fl->size += PFLINES_INCREASE_STEP;
+ }
+
+ fl->lines[fl->len].words = 0;
+ fl->lines[fl->len++].first = first_word;
+
+ return fl;
+}
+
+pflines *pflines_new(void) {
+ // debug(D_PROCFILE, PF_PREFIX ": initializing lines");
+
+ uint32_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_words : PFLINES_INCREASE_STEP;
+
+ pflines *new = malloc(sizeof(pflines) + size * sizeof(ffline));
+ if(unlikely(!new)) return NULL;
+
+ new->len = 0;
+ new->size = size;
+ return new;
+}
+
+void pflines_reset(pflines *fl) {
+ // debug(D_PROCFILE, PF_PREFIX ": reseting lines");
+
+ fl->len = 0;
+}
+
+void pflines_free(pflines *fl) {
+ // debug(D_PROCFILE, PF_PREFIX ": freeing lines");
+
+ free(fl);
+}
+
+
+// ----------------------------------------------------------------------------
+// The procfile
+
+#define PF_CHAR_IS_SEPARATOR ' '
+#define PF_CHAR_IS_NEWLINE 'N'
+#define PF_CHAR_IS_WORD 'W'
+
+void procfile_close(procfile *ff) {
+ debug(D_PROCFILE, PF_PREFIX ": Closing file '%s'", ff->filename);
+
+ if(likely(ff->lines)) pflines_free(ff->lines);
+ if(likely(ff->words)) pfwords_free(ff->words);
+
+ if(likely(ff->fd != -1)) close(ff->fd);
+ free(ff);
+}
+
+procfile *procfile_parser(procfile *ff) {
+ debug(D_PROCFILE, PF_PREFIX ": Parsing file '%s'", ff->filename);
+
+ char *s = ff->data, *e = ff->data, *t = ff->data;
+ uint32_t l = 0, w = 0;
+ e += ff->len;
+
+ ff->lines = pflines_add(ff->lines, w);
+ if(unlikely(!ff->lines)) goto cleanup;
+
+ while(likely(s < e)) {
+ switch(ff->separators[(int)(*s)]) {
+ case PF_CHAR_IS_SEPARATOR:
+ if(likely(s == t)) {
+ // skip all leading white spaces
+ t = ++s;
+ continue;
+ }
+
+ // end of word
+ *s = '\0';
+
+ ff->words = pfwords_add(ff->words, t);
+ if(unlikely(!ff->words)) goto cleanup;
+
+ ff->lines->lines[l].words++;
+ w++;
+
+ t = ++s;
+ continue;
+
+ case PF_CHAR_IS_NEWLINE:
+ // end of line
+ *s = '\0';
+
+ ff->words = pfwords_add(ff->words, t);
+ if(unlikely(!ff->words)) goto cleanup;
+
+ ff->lines->lines[l].words++;
+ w++;
+
+ // debug(D_PROCFILE, PF_PREFIX ": ended line %d with %d words", l, ff->lines->lines[l].words);
+
+ ff->lines = pflines_add(ff->lines, w);
+ if(unlikely(!ff->lines)) goto cleanup;
+ l++;
+
+ t = ++s;
+ continue;
+
+ default:
+ s++;
+ continue;
+ }
+ }
+
+ if(likely(s != t)) {
+ // the last word
+ if(likely(ff->len < ff->size)) *s = '\0';
+ else {
+ // we are going to loose the last byte
+ ff->data[ff->size - 1] = '\0';
+ }
+
+ ff->words = pfwords_add(ff->words, t);
+ if(unlikely(!ff->words)) goto cleanup;
+
+ ff->lines->lines[l].words++;
+ w++;
+ }
+
+ return ff;
+
+cleanup:
+ error(PF_PREFIX ": Failed to parse file '%s'", ff->filename);
+ procfile_close(ff);
+ return NULL;
+}
+
+procfile *procfile_readall(procfile *ff) {
+ debug(D_PROCFILE, PF_PREFIX ": Reading file '%s'.", ff->filename);
+
+ ssize_t s, r = 1, x;
+ ff->len = 0;
+
+ while(likely(r > 0)) {
+ s = ff->len;
+ x = ff->size - s;
+
+ if(!x) {
+ debug(D_PROCFILE, PF_PREFIX ": Expanding data buffer for file '%s'.", ff->filename);
+
+ procfile *new = realloc(ff, sizeof(procfile) + ff->size + PROCFILE_INCREMENT_BUFFER);
+ if(unlikely(!new)) {
+ error(PF_PREFIX ": Cannot allocate memory for file '%s'", ff->filename);
+ procfile_close(ff);
+ return NULL;
+ }
+ ff = new;
+ ff->size += PROCFILE_INCREMENT_BUFFER;
+ }
+
+ debug(D_PROCFILE, "Reading file '%s', from position %ld with length %ld", ff->filename, s, ff->size - s);
+ r = read(ff->fd, &ff->data[s], ff->size - s);
+ if(unlikely(r == -1)) {
+ if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot read from file '%s'", ff->filename);
+ procfile_close(ff);
+ return NULL;
+ }
+
+ ff->len += r;
+ }
+
+ debug(D_PROCFILE, "Rewinding file '%s'", ff->filename);
+ if(unlikely(lseek(ff->fd, 0, SEEK_SET) == -1)) {
+ if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot rewind on file '%s'.", ff->filename);
+ procfile_close(ff);
+ return NULL;
+ }
+
+ pflines_reset(ff->lines);
+ pfwords_reset(ff->words);
+
+ ff = procfile_parser(ff);
+
+ if(unlikely(procfile_adaptive_initial_allocation)) {
+ if(unlikely(ff->len > procfile_max_allocation)) procfile_max_allocation = ff->len;
+ if(unlikely(ff->lines->len > procfile_max_lines)) procfile_max_lines = ff->lines->len;
+ if(unlikely(ff->words->len > procfile_max_words)) procfile_max_words = ff->words->len;
+ }
+
+ debug(D_PROCFILE, "File '%s' updated.", ff->filename);
+ return ff;
+}
+
+static void procfile_set_separators(procfile *ff, const char *separators) {
+ static char def[256] = { [0 ... 255] = 0 };
+ int i;
+
+ if(unlikely(!def[255])) {
+ // this is thread safe
+ // we check that the last byte is non-zero
+ // if it is zero, multiple threads may be executing this at the same time
+ // setting in def[] the exact same values
+ for(i = 0; likely(i < 256) ;i++) {
+ if(unlikely(i == '\n' || i == '\r')) def[i] = PF_CHAR_IS_NEWLINE;
+ else if(unlikely(isspace(i) || !isprint(i))) def[i] = PF_CHAR_IS_SEPARATOR;
+ else def[i] = PF_CHAR_IS_WORD;
+ }
+ }
+
+ // copy the default
+ char *ffs = ff->separators, *ffd = def, *ffe = &def[256];
+ while(likely(ffd != ffe)) *ffs++ = *ffd++;
+
+ // set the separators
+ if(unlikely(!separators)) separators = " \t=|";
+ ffs = ff->separators;
+ const char *s = separators;
+ while(likely(*s)) ffs[(int)*s++] = PF_CHAR_IS_SEPARATOR;
+}
+
+procfile *procfile_open(const char *filename, const char *separators, uint32_t flags) {
+ debug(D_PROCFILE, PF_PREFIX ": Opening file '%s'", filename);
+
+ int fd = open(filename, O_RDONLY, 0666);
+ if(unlikely(fd == -1)) {
+ if(unlikely(!(flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot open file '%s'", filename);
+ return NULL;
+ }
+
+ size_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_allocation : PROCFILE_INCREMENT_BUFFER;
+ procfile *ff = malloc(sizeof(procfile) + size);
+ if(unlikely(!ff)) {
+ error(PF_PREFIX ": Cannot allocate memory for file '%s'", filename);
+ close(fd);
+ return NULL;
+ }
+
+ strncpy(ff->filename, filename, FILENAME_MAX);
+ ff->filename[FILENAME_MAX] = '\0';
+
+ ff->fd = fd;
+ ff->size = size;
+ ff->len = 0;
+ ff->flags = flags;
+
+ ff->lines = pflines_new();
+ ff->words = pfwords_new();
+
+ if(unlikely(!ff->lines || !ff->words)) {
+ error(PF_PREFIX ": Cannot initialize parser for file '%s'", filename);
+ procfile_close(ff);
+ return NULL;
+ }
+
+ procfile_set_separators(ff, separators);
+
+ debug(D_PROCFILE, "File '%s' opened.", filename);
+ return ff;
+}
+
+procfile *procfile_reopen(procfile *ff, const char *filename, const char *separators, uint32_t flags) {
+ if(unlikely(!ff)) return procfile_open(filename, separators, flags);
+
+ if(likely(ff->fd != -1)) close(ff->fd);
+
+ ff->fd = open(filename, O_RDONLY, 0666);
+ if(unlikely(ff->fd == -1)) {
+ procfile_close(ff);
+ return NULL;
+ }
+
+ strncpy(ff->filename, filename, FILENAME_MAX);
+ ff->filename[FILENAME_MAX] = '\0';
+
+ ff->flags = flags;
+
+ // do not do the separators again if NULL is given
+ if(likely(separators)) procfile_set_separators(ff, separators);
+
+ return ff;
+}
+
+// ----------------------------------------------------------------------------
+// example parsing of procfile data
+
+void procfile_print(procfile *ff) {
+ uint32_t lines = procfile_lines(ff), l;
+ uint32_t words, w;
+ char *s;
+
+ debug(D_PROCFILE, "File '%s' with %d lines and %d words", ff->filename, ff->lines->len, ff->words->len);
+
+ for(l = 0; likely(l < lines) ;l++) {
+ words = procfile_linewords(ff, l);
+
+ debug(D_PROCFILE, " line %d starts at word %d and has %d words", l, ff->lines->lines[l].first, ff->lines->lines[l].words);
+
+ for(w = 0; likely(w < words) ;w++) {
+ s = procfile_lineword(ff, l, w);
+ debug(D_PROCFILE, " [%d.%d] '%s'", l, w, s);
+ }
+ }
+}