Merging upstream version 1.11.0+dfsg.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 472 insertions, 0 deletions

diff --git a/libnetdata/procfile/procfile.c b/libnetdata/procfile/procfile.c
new file mode 100644
index 000000000..4a812baab
--- /dev/null
+++ b/libnetdata/procfile/procfile.c
@@ -0,0 +1,472 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "../libnetdata.h"
+
+#define PF_PREFIX "PROCFILE"
+
+#define PFWORDS_INCREASE_STEP 200
+#define PFLINES_INCREASE_STEP 10
+#define PROCFILE_INCREMENT_BUFFER 512
+
+int procfile_open_flags = O_RDONLY;
+
+int procfile_adaptive_initial_allocation = 0;
+
+// if adaptive allocation is set, these store the
+// max values we have seen so far
+size_t procfile_max_lines = PFLINES_INCREASE_STEP;
+size_t procfile_max_words = PFWORDS_INCREASE_STEP;
+size_t procfile_max_allocation = PROCFILE_INCREMENT_BUFFER;
+
+
+// ----------------------------------------------------------------------------
+
+char *procfile_filename(procfile *ff) {
+    if(ff->filename[0]) return ff->filename;
+
+    char buffer[FILENAME_MAX + 1];
+    snprintfz(buffer, FILENAME_MAX, "/proc/self/fd/%d", ff->fd);
+
+    ssize_t l = readlink(buffer, ff->filename, FILENAME_MAX);
+    if(unlikely(l == -1))
+        snprintfz(ff->filename, FILENAME_MAX, "unknown filename for fd %d", ff->fd);
+    else
+        ff->filename[l] = '\0';
+
+    // on non-linux systems, something like this will be needed
+    // fcntl(ff->fd, F_GETPATH, ff->filename)
+
+    return ff->filename;
+}
+
+// ----------------------------------------------------------------------------
+// An array of words
+
+static inline void pfwords_add(procfile *ff, char *str) {
+    // debug(D_PROCFILE, PF_PREFIX ":   adding word No %d: '%s'", fw->len, str);
+
+    pfwords *fw = ff->words;
+    if(unlikely(fw->len == fw->size)) {
+        // debug(D_PROCFILE, PF_PREFIX ":   expanding words");
+
+        ff->words = fw = reallocz(fw, sizeof(pfwords) + (fw->size + PFWORDS_INCREASE_STEP) * sizeof(char *));
+        fw->size += PFWORDS_INCREASE_STEP;
+    }
+
+    fw->words[fw->len++] = str;
+}
+
+NEVERNULL
+static inline pfwords *pfwords_new(void) {
+    // debug(D_PROCFILE, PF_PREFIX ":   initializing words");
+
+    size_t size = (procfile_adaptive_initial_allocation) ? procfile_max_words : PFWORDS_INCREASE_STEP;
+
+    pfwords *new = mallocz(sizeof(pfwords) + size * sizeof(char *));
+    new->len = 0;
+    new->size = size;
+    return new;
+}
+
+static inline void pfwords_reset(pfwords *fw) {
+    // debug(D_PROCFILE, PF_PREFIX ":   reseting words");
+    fw->len = 0;
+}
+
+static inline void pfwords_free(pfwords *fw) {
+    // debug(D_PROCFILE, PF_PREFIX ":   freeing words");
+
+    freez(fw);
+}
+
+
+// ----------------------------------------------------------------------------
+// An array of lines
+
+NEVERNULL
+static inline size_t *pflines_add(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ":   adding line %d at word %d", fl->len, first_word);
+
+    pflines *fl = ff->lines;
+    if(unlikely(fl->len == fl->size)) {
+        // debug(D_PROCFILE, PF_PREFIX ":   expanding lines");
+
+        ff->lines = fl = reallocz(fl, sizeof(pflines) + (fl->size + PFLINES_INCREASE_STEP) * sizeof(ffline));
+        fl->size += PFLINES_INCREASE_STEP;
+    }
+
+    ffline *ffl = &fl->lines[fl->len++];
+    ffl->words = 0;
+    ffl->first = ff->words->len;
+
+    return &ffl->words;
+}
+
+NEVERNULL
+static inline pflines *pflines_new(void) {
+    // debug(D_PROCFILE, PF_PREFIX ":   initializing lines");
+
+    size_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_words : PFLINES_INCREASE_STEP;
+
+    pflines *new = mallocz(sizeof(pflines) + size * sizeof(ffline));
+    new->len = 0;
+    new->size = size;
+    return new;
+}
+
+static inline void pflines_reset(pflines *fl) {
+    // debug(D_PROCFILE, PF_PREFIX ":   reseting lines");
+
+    fl->len = 0;
+}
+
+static inline void pflines_free(pflines *fl) {
+    // debug(D_PROCFILE, PF_PREFIX ":   freeing lines");
+
+    freez(fl);
+}
+
+
+// ----------------------------------------------------------------------------
+// The procfile
+
+void procfile_close(procfile *ff) {
+    if(unlikely(!ff)) return;
+
+    debug(D_PROCFILE, PF_PREFIX ": Closing file '%s'", procfile_filename(ff));
+
+    if(likely(ff->lines)) pflines_free(ff->lines);
+    if(likely(ff->words)) pfwords_free(ff->words);
+
+    if(likely(ff->fd != -1)) close(ff->fd);
+    freez(ff);
+}
+
+NOINLINE
+static void procfile_parser(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ": Parsing file '%s'", ff->filename);
+
+    char  *s = ff->data                 // our current position
+        , *e = &ff->data[ff->len]       // the terminating null
+        , *t = ff->data;                // the first character of a word (or quoted / parenthesized string)
+
+                                        // the look up array to find our type of character
+    PF_CHAR_TYPE *separators = ff->separators;
+
+    char quote = 0;                     // the quote character - only when in quoted string
+    size_t opened = 0;                  // counts the number of open parenthesis
+
+    size_t *line_words = pflines_add(ff);
+
+    while(s < e) {
+        PF_CHAR_TYPE ct = separators[(unsigned char)(*s)];
+
+        // this is faster than a switch()
+        // read more here: http://lazarenko.me/switch/
+        if(likely(ct == PF_CHAR_IS_WORD)) {
+            s++;
+        }
+        else if(likely(ct == PF_CHAR_IS_SEPARATOR)) {
+            if(!quote && !opened) {
+                if (s != t) {
+                    // separator, but we have word before it
+                    *s = '\0';
+                    pfwords_add(ff, t);
+                    (*line_words)++;
+                    t = ++s;
+                }
+                else {
+                    // separator at the beginning
+                    // skip it
+                    t = ++s;
+                }
+            }
+            else {
+                // we are inside a quote or parenthesized string
+                s++;
+            }
+        }
+        else if(likely(ct == PF_CHAR_IS_NEWLINE)) {
+            // end of line
+
+            *s = '\0';
+            pfwords_add(ff, t);
+            (*line_words)++;
+            t = ++s;
+
+            // debug(D_PROCFILE, PF_PREFIX ":   ended line %d with %d words", l, ff->lines->lines[l].words);
+
+            line_words = pflines_add(ff);
+        }
+        else if(likely(ct == PF_CHAR_IS_QUOTE)) {
+            if(unlikely(!quote && s == t)) {
+                // quote opened at the beginning
+                quote = *s;
+                t = ++s;
+            }
+            else if(unlikely(quote && quote == *s)) {
+                // quote closed
+                quote = 0;
+
+                *s = '\0';
+                pfwords_add(ff, t);
+                (*line_words)++;
+                t = ++s;
+            }
+            else
+                s++;
+        }
+        else if(likely(ct == PF_CHAR_IS_OPEN)) {
+            if(s == t) {
+                opened++;
+                t = ++s;
+            }
+            else if(opened) {
+                opened++;
+                s++;
+            }
+            else
+                s++;
+        }
+        else if(likely(ct == PF_CHAR_IS_CLOSE)) {
+            if(opened) {
+                opened--;
+
+                if(!opened) {
+                    *s = '\0';
+                    pfwords_add(ff, t);
+                    (*line_words)++;
+                    t = ++s;
+                }
+                else
+                    s++;
+            }
+            else
+                s++;
+        }
+        else
+            fatal("Internal Error: procfile_readall() does not handle all the cases.");
+    }
+
+    if(likely(s > t && t < e)) {
+        // the last word
+        if(unlikely(ff->len >= ff->size)) {
+            // we are going to loose the last byte
+            s = &ff->data[ff->size - 1];
+        }
+
+        *s = '\0';
+        pfwords_add(ff, t);
+        (*line_words)++;
+        // t = ++s;
+    }
+}
+
+procfile *procfile_readall(procfile *ff) {
+    // debug(D_PROCFILE, PF_PREFIX ": Reading file '%s'.", ff->filename);
+
+    ff->len = 0;    // zero the used size
+    ssize_t r = 1;  // read at least once
+    while(r > 0) {
+        ssize_t s = ff->len;
+        ssize_t x = ff->size - s;
+
+        if(unlikely(!x)) {
+            debug(D_PROCFILE, PF_PREFIX ": Expanding data buffer for file '%s'.", procfile_filename(ff));
+            ff = reallocz(ff, sizeof(procfile) + ff->size + PROCFILE_INCREMENT_BUFFER);
+            ff->size += PROCFILE_INCREMENT_BUFFER;
+        }
+
+        debug(D_PROCFILE, "Reading file '%s', from position %zd with length %zd", procfile_filename(ff), s, (ssize_t)(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' on fd %d", procfile_filename(ff), ff->fd);
+            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'.", procfile_filename(ff));
+        procfile_close(ff);
+        return NULL;
+    }
+
+    pflines_reset(ff->lines);
+    pfwords_reset(ff->words);
+    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;
+}
+
+NOINLINE
+static void procfile_set_separators(procfile *ff, const char *separators) {
+    static PF_CHAR_TYPE def[256];
+    static char initilized = 0;
+
+    if(unlikely(!initilized)) {
+        // this is thread safe
+        // if initialized is zero, multiple threads may be executing
+        // this code at the same time, setting in def[] the exact same values
+        int i = 256;
+        while(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;
+        }
+
+        initilized = 1;
+    }
+
+    // copy the default
+    PF_CHAR_TYPE *ffs = ff->separators, *ffd = def, *ffe = &def[256];
+    while(ffd != ffe)
+        *ffs++ = *ffd++;
+
+    // set the separators
+    if(unlikely(!separators))
+        separators = " \t=|";
+
+    ffs = ff->separators;
+    const char *s = separators;
+    while(*s)
+        ffs[(int)*s++] = PF_CHAR_IS_SEPARATOR;
+}
+
+void procfile_set_quotes(procfile *ff, const char *quotes) {
+    PF_CHAR_TYPE *ffs = ff->separators;
+
+    // remove all quotes
+    int i = 256;
+    while(i--)
+        if(unlikely(ffs[i] == PF_CHAR_IS_QUOTE))
+            ffs[i] = PF_CHAR_IS_WORD;
+
+    // if nothing given, return
+    if(unlikely(!quotes || !*quotes))
+        return;
+
+    // set the quotes
+    const char *s = quotes;
+    while(*s)
+        ffs[(int)*s++] = PF_CHAR_IS_QUOTE;
+}
+
+void procfile_set_open_close(procfile *ff, const char *open, const char *close) {
+    PF_CHAR_TYPE *ffs = ff->separators;
+
+    // remove all open/close
+    int i = 256;
+    while(i--)
+        if(unlikely(ffs[i] == PF_CHAR_IS_OPEN || ffs[i] == PF_CHAR_IS_CLOSE))
+            ffs[i] = PF_CHAR_IS_WORD;
+
+    // if nothing given, return
+    if(unlikely(!open || !*open || !close || !*close))
+        return;
+
+    // set the openings
+    const char *s = open;
+    while(*s)
+        ffs[(int)*s++] = PF_CHAR_IS_OPEN;
+
+    // set the closings
+    s = close;
+    while(*s)
+        ffs[(int)*s++] = PF_CHAR_IS_CLOSE;
+}
+
+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, procfile_open_flags, 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;
+    }
+
+    // info("PROCFILE: opened '%s' on fd %d", filename, fd);
+
+    size_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_allocation : PROCFILE_INCREMENT_BUFFER;
+    procfile *ff = mallocz(sizeof(procfile) + size);
+
+    //strncpyz(ff->filename, filename, FILENAME_MAX);
+    ff->filename[0] = '\0';
+
+    ff->fd = fd;
+    ff->size = size;
+    ff->len = 0;
+    ff->flags = flags;
+
+    ff->lines = pflines_new();
+    ff->words = pfwords_new();
+
+    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)) {
+        // info("PROCFILE: closing fd %d", ff->fd);
+        close(ff->fd);
+    }
+
+    ff->fd = open(filename, procfile_open_flags, 0666);
+    if(unlikely(ff->fd == -1)) {
+        procfile_close(ff);
+        return NULL;
+    }
+
+    // info("PROCFILE: opened '%s' on fd %d", filename, ff->fd);
+
+    //strncpyz(ff->filename, filename, FILENAME_MAX);
+    ff->filename[0] = '\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) {
+    size_t lines = procfile_lines(ff), l;
+    char *s;
+    (void)s;
+
+    debug(D_PROCFILE, "File '%s' with %zu lines and %zu words", procfile_filename(ff), ff->lines->len, ff->words->len);
+
+    for(l = 0; likely(l < lines) ;l++) {
+        size_t words = procfile_linewords(ff, l);
+
+        debug(D_PROCFILE, " line %zu starts at word %zu and has %zu words", l, ff->lines->lines[l].first, ff->lines->lines[l].words);
+
+        size_t w;
+        for(w = 0; likely(w < words) ;w++) {
+            s = procfile_lineword(ff, l, w);
+            debug(D_PROCFILE, "     [%zu.%zu] '%s'", l, w, s);
+        }
+    }
+}